BXP Bxp, Inc. - 10-K

RISK FACTORS

UNRESOLVED STAFF COMMENTS

CYBERSECURITY

PROPERTIES

LEGAL PROCEEDINGS

MINE SAFETY DISCLOSURES

PART II

MARKET FOR REGISTRANT’S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

RESERVED

MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE

CONTROLS AND PROCEDURES

OTHER INFORMATION

DISCLOSURE REGARDING FOREIGN JURISDICTIONS THAT PREVENT INSPECTIONS

PART III

DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE

EXECUTIVE COMPENSATION

SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS

CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE

PRINCIPAL ACCOUNTANT FEES AND SERVICES

PART IV

EXHIBITS AND FINANCIAL STATEMENT SCHEDULES

FORM 10-K SUMMARY

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Summary of Risk Factors

The risk factors detailed in Item 1A titled “Risk Factors” in this Annual Report on Form 10-K are the risks that we believe are material to our investors and a reader should carefully consider them. Those risks are not all of the risks we face and other factors not presently known to us or that we currently believe are immaterial may also affect our business if they occur. The following is a summary of the risk factors detailed in Item 1A:

• Our performance depends upon the economic conditions, particularly the supply and demand characteristics, of our markets—Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC.

• Market and economic volatility due to adverse economic and political conditions, health crises or dislocations in the credit markets could have a material adverse effect on our results of operations, financial condition and ability to pay dividends and/or distributions.

• Our success depends on key personnel whose continued service is not guaranteed.

• Our performance and value are subject to risks associated with our real estate assets and with the real estate industry, including, without limitation:

• potential difficulties or delays renewing leases or re-leasing space;

• sustained changes in client preferences and space utilization from full-time, collective in-person work environments to hybrid or remote work models and/or changes from workforce reduction due to artificial intelligence, which could decrease overall demand for workplaces and negatively impact market rental rates and property values;

• potential delays in completion of development and redevelopment projects due to supply chain disruptions and labor shortages; and

• potential increases in costs to maintain, renovate and develop our properties related to inflation.

• We face potential adverse effects from major clients’ bankruptcies or insolvencies.

• Our actual costs to develop properties may exceed our budgeted costs.

• Our use of joint ventures may limit our control over jointly owned investments and limit our flexibility to acquire other assets.

• We face risks associated with the use of debt to fund acquisitions and developments, including refinancing risk.

• Our maturing debt bears interest at lower rates than the current market rates, which has increased, and may continue to increase our interest costs which could adversely impact our ability to refinance existing debt or sell assets on favorable terms or at all.

• Covenants in our debt agreements could adversely affect our financial condition.

• Our degree of leverage could limit our ability to obtain additional financing or affect the market price of our equity and debt securities.

• We face risks associated with security breaches, incidents and compromises through cyber attacks, cyber intrusions or otherwise, as well as other significant disruptions of our information technology (IT) networks and related systems.

• The use of technology based on artificial intelligence and machine learning presents risks and challenges that may adversely affect our business and results of operations.

• We face risks associated with climate change and severe weather events, as well as the regulatory efforts intended to reduce the effects of climate change.

• Potential liability for environmental contamination could result in substantial costs.

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• Some potential losses are not covered by insurance.

• Our involvement in legal proceedings and other claims may result in substantial monetary and other costs that have a material adverse effect on our results of operations.

• We face risks associated with BXP’s status as a real estate investment trust (REIT), including, without limitation:

• failure to qualify as a REIT would cause BXP to be taxed as a corporation, which would substantially reduce funds available for payment of dividends;

• possible adverse state and local tax audits and changes in state and local tax laws could result in increased tax costs that could adversely affect our financial condition and results of operations and the amount of cash available for the payment of dividends and distributions to our securityholders; and

• in order to maintain BXP’s REIT status, we may be forced to borrow funds during unfavorable market conditions.

This section contains forward-looking statements. You should refer to the explanation of the qualifications and limitations on forward-looking statements beginning on page 52 .

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PART I.

Item 1 . Business

General

BXP, a Delaware corporation, is a fully integrated, self-administered and self-managed REIT, and it is one of the largest publicly-traded office REITs (based on total market capitalization as of December 31, 2025) in the United States that develops, owns and manages primarily premier workplaces. BXP was formed in 1997 to succeed the real estate development, redevelopment, acquisition, management, operating and leasing businesses associated with the predecessor company founded by Mortimer B. Zuckerman and Edward H. Linde in 1970.

Our properties are concentrated in six dynamic gateway markets—Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC. At December 31, 2025, we owned or had joint venture interests in a portfolio of 179 commercial real estate properties, aggregating approximately 52.6 million net rentable square feet of primarily premier workplaces, including eight properties under construction/redevelopment totaling approximately 3.5 million net rentable square feet. As of December 31, 2025, our properties consisted of:

• 157 office properties (including four properties under construction/redevelopment);

• 14 retail properties (including one property under construction);

• seven residential properties (including three properties under construction); and

• one hotel.

We consider premier workplaces to be well-located buildings that are modern structures or have been modernized to compete with newer buildings, are professionally managed and maintained, and offer a number and type of amenities that are in high demand by clients that are focused on the importance of the physical work environment in recruiting and retaining the best and brightest employees. As such, these properties attract creditworthy clients and command upper-tier rental rates in their markets. We do not consider the expression “premier workplaces” a classification of our properties in accordance with any standard listing criteria in the real estate industry. We therefore caution investors that our use and definition of “premier workplaces” may be different than the use and definition of similar expressions and traditional classifications that may be used by other companies.

We are a full-service real estate company, with substantial in-house expertise and resources in acquisitions, development, financing, capital markets, construction management, property management, marketing, leasing, accounting, risk management, tax and legal services. For this reason, we refer to our tenants as “clients” due to the many facets of our continuous engagements with them, which span beyond the usual tenant/landlord relationship. Throughout this Annual Report, we use the terms “tenant” and “client” interchangeably.

BXP manages BPLP as its sole general partner. Our principal executive office and Boston regional office are located at The Prudential Center, 800 Boylston Street, Suite 1900, Boston, Massachusetts 02199 and our telephone number is (617) 236-3300. In addition, we have regional offices at 2800 28th Street, Santa Monica, California 90405, 599 Lexington Avenue, New York, New York 10022, Two Embarcadero Center, San Francisco, California 94111, 1001 Fourth Avenue, Seattle, Washington 98154 and 2200 Pennsylvania Avenue NW, Washington, DC 20037.

Our internet address is http://www.bxp.com. On our website, you can obtain free copies of our Annual Reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, including exhibits, and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended, as soon as reasonably practicable after we electronically file such material with, or furnish it to, the Securities and Exchange Commission, or the SEC. You may also obtain BXP’s and BPLP’s reports by accessing the EDGAR database at the SEC’s website at http://www.sec.gov, or we will furnish an electronic or paper copy of these reports free of charge upon written request to: Investor Relations, BXP, Inc., Prudential Center, 800 Boylston Street, Suite 1900, Boston, Massachusetts 02199. “Boston Properties” is a registered trademark, BXP is a registered trademark, and the “bxp” logo is a registered trademark, in all cases, owned by BPLP.

Boston Properties Limited Partnership

BPLP is a Delaware limited partnership organized in 1997, and the entity through which BXP conducts substantially all of its business and owns, either directly or through subsidiaries, substantially all of its assets. BXP is the sole general partner of BPLP and, as of February 20, 2026, the owner of approximately 89.4% of the economic interests in BPLP. Economic interest was calculated as the number of common partnership units of BPLP

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owned by BXP as a percentage of the sum of (1) the actual aggregate number of outstanding common partnership units of BPLP and (2) the number of common units issuable upon conversion of all outstanding long term incentive plan units of BPLP (“LTIP Units”), for which all performance conditions have been satisfied for such conversion. We exclude from (1) and (2) above other LTIP Units issued in the form of Multi-Year Long-Term Incentive Plan Awards in 2024 or later (“MYLTIP Awards or MYLTIP Units”) and 2025 Outperformance Plan Awards (“2025 OPP Awards or 2025 OPP Units”), which remain subject to performance conditions. An LTIP Unit is generally the economic equivalent of a share of BXP’s restricted common stock, although LTIP Units issued in the form of MYLTIP Awards and 2025 OPP Awards are only entitled to receive one-tenth (1/10th) of the regular quarterly distributions (and no special distributions) prior to being earned.

Transactions During 2025

Acquisitions

During the year ended December 31, 2025, we acquired 2100 M Street, a vacant office building, located in Washington, DC, for a purchase price, including transaction costs, of approximately $55.9 million of cash. We intend to redevelop this site in the future (See Note 3 to the Consolidated Financial Statements).

Dispositions and Impairments

During the year ended December 31, 2025, excluding our unconsolidated joint ventures, we completed eight sales transactions for an ag gregate gross sales price of approximately $702.6 million, resulting in net proceeds of approximately $682.5 million and gains on sales of real estate of $175.0 million and $177.6 million for BXP and BPLP, respectively (See Note 3 to the Consolidated Financial Statements). .

During the year ended December 31, 2025 , we evaluated the consolidated properties approved by BXP’s Board of Directors (or a committee thereof) for sale to third-parties, which resulted in recognized impairment losses of approximately $85.8 million and $82.9 million for BXP and BPLP, respectively (See Notes 2 and 3 to the Consolidated Financial Statements).

Developments /Redevelopments

During the year ended December 31, 2025, we commenced development/redevelopment of four properties, including 343 Madison Avenue in New York City, New York, aggregating approximately 1.9 million in estimated net rentable square feet when complete. Our share of the aggregated estimated total investment to complete these properties is approximately $2.1 billion. We also partially or fully placed in-service four properties that totaled approximately 727,000 net rentable square feet (See Notes 3 and 6 to the Consolidated Financial Statements).

As of December 31, 2025, we had eight properties under construction/redevelopment, aggregating approximately 3.5 million in estimated net rentable square feet when completed. We estimate our share of the aggregate estimated total investment to complete these projects is approximately $3.9 billion, of which approximately $2.5 billion remained to be invested as of December 31, 2025. The total development pipeline, including office, laboratory/life sciences and retail developments, but excluding our residential developments, is 61% pre-leased as of February 20, 2026. For a detailed list of the properties under construction/redevelopment see “Liquidity and Capital Resources” within “Item 7—Management’s Discussion and Analysis of Financial Condition and Results of Operations.”

Debt

During the year ended December 31, 2025, BXP further strengthened its balance sheet by addressing debt maturities and sourcing additional liquidity in the capital markets. In the aggregate, excluding our unconsolidated joint ventures, our debt market activities totaled approximately $4.2 billion, underscoring BXP’s consistent access to debt capital. For additional details on each of the transactions listed below, refer to Note 7 to the Consolidated Financial Statements.

Notable transactions during 2025 include:

• Repaid $850.0 million of 3.20% unsecured senior notes due January 15, 2025,

• Upsized the unsecured commercial paper program from $500.0 million to $750.0 million in March 2025,

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• Extended the maturity date for the $700.0 million unsecured term loan to 2030 (inclusive of extension options) in March 2025,

• Upsized the amended and restated revolving credit agreement from $2.0 billion to $2.25 billion and extended its maturity date to 2030 in March 2025, and

• Issued $1.0 billion of 2.00% unsecured exchangeable senior notes due 2030 in September 2025.

Hedging Transaction

On April 8, 2025, BPLP entered into an interest rate swap contract with a notional amount of $300.0 million to replace $300.0 million of interest rate swap contracts that expired on April 1, 2025. The interest rate swap was entered into to fix Daily Simple SOFR, at a fixed interest rate of 3.6775% per annum for the period commencing on April 7, 2025, the effective date, and ending on April 6, 2026 (See Note 8 to the Consolidated Financial Statements).

Equity Transactions

During the year ended December 31, 2025, BXP acquired an aggregate of 291,040 common units of limited partnership interest, including a total of 87,398 common units issued upon the conversion of LTIP Units, 2012 outperformance plan awards (“2012 OPP Units”) and 2013 - 2021 multi-year, long-term incentive program awards, presented by the holders for redemption, in exchange for an equal number of shares of BXP common stock.

Investments in Unconsolidated Joint Ventures

For additional details on each of the transactions listed below, refer to Note 6 to the Consolidated Financial Statements.

During the year ended December 31, 2025, our unconsolidated joint ventures further strengthened their balance sheets by addressing debt maturities and sourcing additional liquidity in the capital markets. In the aggregate, their debt market activities totaled approximately $1.2 billion of which our share was approximately $0.5 billion. Notable transactions during 2025 include:

• Executed a new $252.0 million non-recourse CMBS financing secured by our 7750 Wisconsin Avenue joint venture in Bethesda, Maryland in February 2025. This new loan was used to repay the existing $252.0 million construction loan. We have a 50% ownership interest in the joint venture.

• Executed a new $225.0 million construction loan secured by our 290 Coles Street joint venture in Jersey City, New Jersey in March 2025. We have a 19.46% ownership interest in the joint venture.

• Executed a new $98.7 million construction loan secured by our 17 Hartwell Street joint venture in Lexington, Massachusetts in June 2025. We have a 20% ownership interest in the joint venture.

• Executed a new $465.0 million non-recourse CMBS financing secured by our Hub on Causeway - Podium and 100 Causeway Street joint ventures in Boston, Massachusetts in October 2025. This new loan was used to repay the existing loans aggregating approximately $490.0 million. We have a 50% ownership interest in the joint ventures.

• Executed a (1) new $108.0 million senior loan and (2) $50.0 million mezzanine loan secured by our 3 Hudson Boulevard joint venture in New York City, New York in October 2025. These new loans were used to repay the existing $80.0 million loan that was provided by us to the joint venture. We have a 25% ownership interest in the joint venture and are the lender for the mezzanine loan.

• Repaid the approximately $198.4 million construction loan secured by our Dock 72 joint venture in Brooklyn, New York in October 2025. We have a 50% ownership interest in the joint venture.

During the year ended December 31, 2025, we completed three sale transactions related to our investments in unconsolidated joint ventures. Our share of the ag gregate gross sales price was approximately $237.7 million, resulting in our share of net proceeds of approximately $170.2 million. We recognized gains on sales related to these transactions of approximately $53.7 million, which has been included within Loss from Unconsolidated Joint Ventures on the Consolidated Financial Statements.

During the year ended December 31, 2025, we evaluated key impairment indicators related to certain investments in unconsolidated joint ventures (See Note 2 to the Consolidated Financial Statements). This

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evaluation, including a pending offer from a third-party, resulted in our determination that the decline in value for the joint venture that owns Gateway Commons was other-than-temporary. As a result, we recognized an other-than-temporary impairment loss on our investment in Gateway Commons of approximately $145.1 million.

Noncontrolling Interest

On August 27, 2025, we acquired our partner’s 45% ownership interest in the consolidated entity that is developing the 343 Madison Avenue project located in New York City, New York for approximately $43.5 million of cash. The acquisition price equaled the partner’s aggregate unreturned capital contributions to the joint venture. Prior to the acquisition, we had a 55% ownership interest in the joint venture.

Stock Option and Incentive Plan

For additional details on each of the transactions listed below, refer to Note 15 to the Consolidated Financial Statements.

On January 22, 2025, BXP’s Compensation Committee approved the 2025 Multi-Year Long-Term Incentive Program (the “2025 MYLTIP”) awards under the BXP, Inc. 2021 Stock Incentive Plan (the “2021 Plan”) to certain executive officers of BXP. Under Accounting Standards Codification (“ASC”) 718 “Compensation – Stock Compensation,” (“ASC 718”) the 2025 MYLTIP awards have an aggregate value of approximately $12.7 million, which amount will generally be amortized into earnings under the graded vesting method.

On January 31, 2025, the three-year measurement period for our 2022 MYLTIP awards ended and, based on BXP’s absolute and relative total shareholder return (“TSR”) performance, the final payout was determined to be 59% of target, or an aggregate of approximately $5.4 million (after giving effect to employee separations). As a result, an aggregate of 177,919 2022 MYLTIP Units that had been previously granted were automatically forfeited.

On December 22, 2025, BXP’s Compensation Committee approved the 2025 OPP Awards. Under the 2025 OPP Awards, performance and service-based equity awards were granted to certain members of BXP’s senior leadership team. The awards were issued pursuant to the 2021 Plan in the form of LTIP Units and consist of an opportunity to earn up to an aggregate of 711,864 LTIP Units. The number of LTIP Units reflects the maximum that may be earned for achieving the highest level of performance and satisfying the service-based vesting requirements. Under ASC 718 the 2025 OPP Awards have an aggregate value of approximately $31.9 million, which amount will generally be amortized into earnings under the graded vesting attribution method.

Business and Growth Strategies

Business Strategies

Our primary business objective is to maximize return on investment to provide our investors with the greatest possible total return at all points of the economic cycle. Our long-term strategies to achieve this objective are:

• to target a few carefully selected dynamic gateway markets—Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC—and to be one of the leading, if not the leading, developers, owners and managers in each of those markets with a full-service office in each market providing property management, leasing, development, construction and legal expertise. We select markets and submarkets with a diverse economic base and a deep pool of prospective clients in various industries and where clients have demonstrated a preference for premier workplaces and other facilities. Additionally, our markets have historically been able to recruit new talent to them and help sustain job growth that results in growth in rental rates and occupancy over time;

• to emphasize markets and submarkets within those markets where the difficulty of receiving the necessary approvals for development and the necessary financing constitute high barriers to the creation of new supply, and where skill, financial strength and diligence are required to successfully develop, finance and manage high-quality office as well as selected life sciences, retail and residential space;

• to take on complex, technically challenging development projects, leveraging the skills of our management team to successfully develop, acquire or reposition properties that other organizations may not have the capacity or resources to pursue;

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• to own and develop high-quality real estate designed to meet the demands of today’s clients who require sophisticated telecommunications and related infrastructure, support services, sustainable features and amenities, including those amenities that enrich in-person experiences and support a hybrid work environment, and to manage those facilities so as to become the landlord of choice for both existing and prospective clients;

• to opportunistically acquire assets that increase our market share in the markets in which we have chosen to concentrate, as well as potential new markets, which exhibit an opportunity to improve returns through repositioning (through a combination of capital improvements and shift in marketing strategy), changes in management focus and leasing;

• to explore joint venture or lending opportunities with existing property owners located in desirable locations, who seek to benefit from the depth of development and management expertise we are able to provide and our access to capital;

• to pursue on a selective basis the sale of properties or interests therein, including core properties, to either (1) take advantage of the demand for our premier properties and realize the value we have created or (2) pare from our portfolio properties that we believe have slower future growth potential;

• to seek third-party development contracts to enable us to retain and utilize our existing development and construction management staff, especially when our internal development is less active or when new development is less-warranted due to market conditions; and

• to enhance our capital structure through our access to a variety of sources of equity and debt capital and proactively manage our debt expirations.

From time to time, in response to one or more macroeconomic or other external factors, we refine our plans for achieving one or more elements of our overall strategy. At our September 2025 Investor Day, we detailed a three-year action plan focused on near-term earnings growth by leveraging BXP's operational expertise and portfolio of premier workplaces within our core gateway markets to:

• grow occupancy;

• develop premier assets with a focus on projects underway and a selective approach to future opportunities;

• execute on a multi-year asset sales program to dispose of non-income producing land, select residential, and non-strategic and select strategic office assets, with proceeds designated to reduce leverage and fund our development pipeline; and

• secure private equity partnerships on select assets to complement other funding sources and increase investment yields.

We believe the components of this strategic action plan align with our broader, long-term strategy of maintaining leadership in core markets, prudently growing the portfolio, and disciplined capital allocation to drive shareholder value. We may achieve the goals underlying this strategic action plan through a variety of methods and the timing, extent and impact of any transactions that we have or will undertake while implementing this strategic action plan may vary and evolve.

Growth Strategies

External Growth Strategies

We believe that our development experience, our organizational depth, utilization of our joint venture partner relationships and our balance sheet position us to continue to selectively develop a range of premier workplaces, including high-rise urban developments, mixed-use developments (including office, residential and retail), low-rise suburban office and residential properties, within budget and on schedule. We believe we are also well-positioned to achieve external growth through acquisitions. From time to time, we remove from service select office assets for which we believe we have better uses, such as residential developments. Other factors that contribute to our competitive position include:

• our control of sites in our markets that could support, as of December 31, 2025, approximately 13.6 million and 4.7 million of additional square feet of new office and residential developments, respectively;

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• our reputation gained through 56 years of successful operations and the stability and strength of our existing portfolio of properties;

• our relationships with leading national corporations, universities and public institutions, including government agencies, seeking new facilities and development services;

• our relationships with nationally recognized financial institutions that provide capital to the real estate industry;

• our track record and reputation for executing acquisitions efficiently provide comfort to domestic and foreign institutions, private investors and business entities who seek to sell commercial real estate in our market areas;

• our ability to act quickly on due diligence and financing;

• our relationships with institutional buyers and sellers of high-quality real estate assets;

• our ability to procure entitlements from multiple municipalities to develop and/or sell sites and attract land owners to sell to or partner with us; and

• our relationship with domestic and foreign investors who seek to partner with companies like ours.

Opportunities to execute our external growth strategy fall into three categories:

• Development in selected submarkets. We believe the selective development of well-positioned premier workplaces, as well as residential buildings and mixed-use complexes, may be justified in certain of our markets. We believe in acquiring land after taking into consideration timing factors relating to economic cycles and in response to market conditions that should allow for its development at the appropriate time. While we purposely concentrate in markets with high barriers-to-entry, we have demonstrated throughout our 56-year history an ability to make carefully timed land acquisitions in submarkets where we can become one of the market leaders in establishing rent and other business terms. We believe that there are opportunities at key locations in our existing and other markets for a well-capitalized developer to acquire land or buildings with development or redevelopment potential.

We seek complex projects where we can add value through the efforts of our experienced and skilled management team leading to attractive returns on investment. In the past, we have been particularly successful at acquiring sites or options to purchase sites that need governmental approvals for development. Because of our development expertise, knowledge of the governmental approval process and reputation for quality development with local government regulatory bodies, we generally have been able to secure the permits necessary to allow development and to profit from the resulting increase in land value.

Our strong regional relationships and recognized development expertise have also enabled us to capitalize on unique build-to-suit opportunities. We intend to seek and expect to continue to be presented with such opportunities in the near term allowing us to earn relatively significant returns on these development opportunities through multiple business cycles.

• Acquisition of assets and portfolios of assets from institutions, including lenders, or individuals. We believe that due to our size, management strength and reputation, we are well positioned to acquire portfolios of assets or individual properties from institutions or individuals if valuations meet our criteria. In addition, we believe that our market knowledge, our liquidity and access to capital may provide us with a competitive advantage when pursuing acquisitions. Opportunities to acquire properties may also come through the purchase of first mortgage or mezzanine debt. We are also able to appeal to sellers wishing to contribute on a tax-deferred basis their ownership of property for equity in a diversified real estate operating company that offers liquidity through access to the public equity markets in addition to a quarterly distribution. Our ability to offer common and preferred units of limited partnership in BPLP to sellers who would otherwise recognize a taxable gain upon a sale of assets for cash or BXP’s common stock may facilitate these types of acquisitions on a tax-efficient basis. Existing promulgated Treasury regulations may limit the tax benefits previously available to sellers in some variations of these transactions.

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• Acquisition of underperforming assets and portfolios of assets . We believe that because of our in-depth market knowledge and development experience in each of our markets, our national reputation with brokers, financial institutions, owners of real estate and others involved in the real estate market and our access to competitively-priced capital, we are well-positioned to identify and acquire existing, underperforming properties for competitive prices and to add significant additional value to such properties through our effective marketing strategies, repositioning/redevelopment expertise and a responsive property management program.

Internal Growth Strategies

We believe that opportunities will exist to increase cash flow from our existing properties through an increase in occupancy and rental rates because they are of high quality and in desirable locations. Additionally, our markets have diversified economies that have historically experienced job growth and increased use of office space, resulting in growth in rental rates and occupancy over time. Our strategy for maximizing the benefits from these opportunities is three-fold: (1) to provide high-quality property management services using our employees in order to encourage clients to renew, expand and relocate in our properties, (2) to achieve speed and transaction cost efficiency in replacing departing clients through the use of in-house services for marketing, lease negotiation and construction of tenant and capital improvements and (3) to work with new or existing clients with space expansion or contraction needs, leveraging our expertise and clustering of assets to maximize the cash flow from our assets. We expect to continue our internal growth as a result of our ability to:

• Carefully select submarkets and cultivate long-term relationships with creditworthy clients. In choosing locations for our properties, we have paid particular attention to transportation and commuting patterns, physical environment, adjacency to established business centers and amenities, proximity to sources of business growth and other local factors that we believe our clients demand.

At December 31, 2025, the weighted-average lease term of our in-place leases based on square feet, including leases signed by our unconsolidated joint ventures, was approximately 7.9 years and we continue to cultivate long-term leasing relationships with a diverse base of high-quality, financially stable clients. In 2025, we executed approximately 5.6 million square feet of leases with a weighted-average lease term of 10.1 years. Based on leases in place at December 31, 2025, leases with respect to approximately 2.6%, or approximately 1.2 million square feet, of the total square feet in our portfolio, including unconsolidated joint ventures but excluding Gateway Commons and North First Business Park, will expire in calendar year 2026.

• Directly manage our office properties to maximize the potential for client retention. We provide property management services ourselves, rather than contracting for this service, to maintain awareness of and responsiveness to client needs. We and our properties also benefit from cost efficiencies produced by an experienced work force attentive to preventive maintenance and energy management and from our continuing programs to assure that our property management personnel at all levels remain aware of their important role in client relations. In addition, we reinvest in our properties by adding new services and amenities that are desirable to our clients.

• Replace clients quickly at best available market terms and lowest possible transaction costs . We believe that we are well-positioned to attract new clients and achieve relatively high rental and occupancy rates as a result of our well-located, well-designed and well-maintained properties, our reputation for high-quality building services and responsiveness to clients, and our ability to offer expansion and relocation alternatives within our submarkets.

• Extend terms of existing leases to existing clients prior to expiration . We have also successfully structured early client renewals, which have reduced the cost associated with lease downtime while securing the tenancy of our highest quality credit-worthy clients on a long-term basis and enhancing relationships.

• Re-development of existing assets. We believe the select re-development of assets within our portfolio, where through the ability to increase the building size and/or to increase cash flow and generate appropriate returns on incremental investment after consideration of the asset’s current and future cash flows, may be desirable. This generally occurs in situations in which we are able to increase the building’s size, improve building systems, including conversion to higher yielding uses, and sustainability features, and/or add client amenities, thereby increasing client demand, generating acceptable returns

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on incremental investment and enhancing the long-term value of the property and the company. In the past, we have been particularly successful at gaining local government approval for increased density at several of our assets, providing the opportunity to enhance value at a particular location. Our strong regional relationships and recognized re-development expertise have enabled us to capitalize on unique build-to-suit opportunities. We intend to seek and expect to continue to be presented with such opportunities in the near term allowing us to earn attractive returns on these development opportunities through multiple business cycles.

Sustainability

Our Strategy

We are committed to maximizing long-term value for our shareholders through, among other strategies, actively working to promote our growth and operations sustainably and responsibly across our six dynamic gateway markets. BXP’s sustainability strategy is to conduct our business, the development, ownership and operation of new and existing buildings, in a manner that contributes to positive outcomes for our clients, shareholders, employees and the communities in which we operate (collectively, our “stakeholders”). We are focused on developing and maintaining healthy, high-performance buildings, while simultaneously mitigating operational costs and the potential external impacts of energy, water, waste, and climate change. We undertake electric, steam, and natural gas efficiency projects and procurement initiatives to reduce energy-related operating expense growth and primary fossil fuel consumption. These initiatives have also contributed to lower greenhouse gas (“GHG”) emissions and compliance with building performance standards in the New York and Boston markets. Through our efforts, we demonstrate that operating and developing commercial real estate can be conducted with a conscious regard for the environment while mutually benefiting our stakeholders.

Sustainability Leadership

BXP is a widely recognized industry leader in sustainability, and our 2025 highlights include:

• BXP achieved carbon-neutral operations for GHG emissions Scopes 1 and 2

• BXP ranked among the top real estate companies in the GRESB assessment, earning a tenth consecutive 5-star rating. 2025 was the 14th consecutive year that BXP earned the GRESB “Green Star” designation

• BXP maintained an MSCI rating of “AA” and a CDP score of “B”

• BXP was named to Newsweek’s America’s Most Responsible Companies 2026 for the sixth consecutive year, ranking in the top half of 600 companies, and was also named to Newsweek’s America’s Greenest Companies 2026 with a 5-star rating

• BXP was named a Fitwel Best in Building Health Award winner by the Center for Active Design for the ninth time

• BXP earned the City of Boston’s Building Emissions Reduction and Disclosure Ordinance's (BERDO) Energy Efficiency Spotlight, highlighting our retro-commissioning efforts in Boston

• BXP was named a Sustainalytics Low Carbon Leader

• BXP continued its tenure as an inaugural Platinum Level Green Lease Leader by the Institute for Market Transformation and the U.S. Department of Energy

Our leadership position is due, in part, to our establishment of environmental goals, the periodic reporting of progress toward our goals and the achievement of these goals, which we report in an annual Sustainability & Impact Report that is made available on our website at http://www.bxp.com under the heading “Commitment”. We have publicly adopted energy, water, building certification, waste and GHG emissions goals, including a commitment to achieving carbon-neutral operations (for direct and indirect Scope 1 and Scope 2 GHG emissions) by the end of 2025 from our occupied and actively managed buildings where we have operational control. We have also provided climate-related disclosures aligned with the recommendations of the Task Force on Climate-Related Financial Disclosures (“TCFD”). Detailed information on these goals and targets and our TCFD disclosures are included in our Sustainability & Impact Reports. We expect to publish our next report in April 2026.

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The Sustainability & Impact Reports and the related information contained on our website (or that can be accessed through our website) are not incorporated by reference into this Annual Report on Form 10-K.

Sustainability Accounting Standards Board (“SASB”) Disclosures

The Real Estate Sustainability Accounting Standard issued by SASB in 2018 proposed sustainability accounting metrics designed for disclosure in mandatory filings, such as the Annual Report on Form 10-K, and serves as the framework against which we have aligned our disclosures for sustainability information. The recommended energy and water management activity metrics for the real estate industry include energy consumption data coverage as a percentage of floor area (“Energy Intensity”); percentage of the eligible portfolio that is certified ENERGY STAR® (“ENERGY STAR certified”); total energy consumed by portfolio area (“Total Energy Consumption”); water withdrawal as a percentage of total floor area (“Water Intensity”); and total water withdrawn by portfolio area (“Total Water Consumption”). Our energy and water data is collected from utility bills and submeters and is assured by an independent, third-party assurance expert, which includes all 2024 SASB energy and water metrics. During the 2025 calendar year, 64 buildings representing 50% of BXP’s total in-service portfolio were ENERGY STAR certified. A licensed professional has verified all ENERGY STAR applications.

The charts below detail our Energy Intensity, Total Energy Consumption, Water Intensity and Total Water Consumption for 2015 through 2024 for which data were available on occupied and actively managed office buildings where we had operational control. 1,2,3,4,5,6

(1) Full 2025 calendar year energy and water data will not be available and assured by a third party until April 2026. Therefore, 2024 is the most recent year for which complete and third-party assured energy and water data is available.

(2) The charts reflect the performance of our occupied and actively managed office portfolio. We define “occupied buildings” as those with no more than 50% vacancy. Actively managed office buildings are multi-tenant buildings over which we have operational control of building system performance and investment decisions. At the end of the 2024 calendar year, our occupied and actively managed office portfolio included 75 buildings totaling 39.6 million gross square feet, and it accounted for approximately 73% of BXP’s total in-service portfolio by area.

(3) Floor area is considered to have complete energy consumption data coverage when we obtain energy consumption data (i.e., energy types and amounts consumed) for all types of energy consumed in the relevant floor area during the calendar year, regardless of when such data was obtained.

(4) The scope of energy includes energy purchased from sources external to us and our clients or produced by us or our clients and energy from all sources, including fuel, gas, electricity and steam. Energy use intensity (kBtu/SF) has been weather-normalized.

(5) Water sources include surface water (including water from wetlands, rivers, lakes and oceans), groundwater, rainwater collected directly and stored by BXP, municipal water supplies or supply from other water utilities.

(6) 2020 and 2021 data reflect the combined impacts of efficiency measures and reduced physical occupancy due to the COVID-19 pandemic.

Human Capital Management

As of December 31, 2025, we had 714 non-union employees and 112 union employees. Because the unions control the primary aspects of the hiring process, except as otherwise noted, all data provided in this Human Capital Management section refers to BXP’s non-union employee workforce only.

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Our operational and financial performance depends on the talents, energy, experience and well-being of our employees. Our ability to attract and retain talented people depends on a number of factors, including work environment, career development and professional training, compensation and benefits, and the health, safety and wellness of our employees.

Our workforce provides a strategic business advantage as it is one of our most valuable assets. We are committed to the quality, growth and development of our people as part of our strategy to drive long-term value for our shareholders. We aim to ensure that all employees have the opportunity to make their maximum contribution to us and to their own career goals. It has been, and will continue to be, our policy to recruit, hire, assign, promote and train in all job titles without regard to race, national origin, religion, age, color, sex, sexual orientation, gender identity, disability, protected veteran status, or any other characteristic protected by local, state, or federal laws, rules, or regulations. Our hiring practices do not, and have not, included quotas or numerical targets based on any of these characteristics.

Culture & Employee Engagement

We believe that the success of our business is tied to the quality of our workforce, and we strive to maintain a corporate environment without losing the entrepreneurial spirit with which we were founded more than 55 years ago. By providing a quality workplace and comprehensive benefit programs, we recognize the commitment of our employees to bring their talent, energy and experience to us. Our continued success will depend on our employees’ expertise and dedication. Our workforce, as referred to in this section, excludes intern employees and union employees for which the unions control primary aspects of the hiring process.

We periodically conduct employee engagement surveys to monitor our employees’ satisfaction in different aspects of their employment, including company performance, leadership, communication, career development and benefits offerings. Past employee responsiveness to the engagement surveys has been consistently high and the results help inform us on matters that our employees view as key contributors to a positive work experience. Based on the most recent employee engagement survey conducted in 2025, with a 93% response rate, the overall company-wide result was a “favorable” rating. The results affirmed that BXP is healthy across core areas such as company performance, leadership and management. We intend to continue to periodically evaluate employee engagement as needed on a meaningful basis.

Another indicator of the success of our efforts in the workplace is the long tenure of our employees. Approximately 34% of our employees have worked at BXP for ten or more years. The average tenure of our employees is approximately 9.8 years and that of our officers is 18.3 years. In 2025, our voluntary workforce turnover rate was 7.6%.

Career Development & Training

We invest significant resources in our employees’ personal and professional growth and development and provide a wide range of tools and development opportunities that build and strengthen employees’ leadership and professional skills. These development opportunities include in-person and virtual training sessions, in-house learning opportunities, various management trainings, departmental conferences, executive town halls and external programs. We foster an environment of growth and internal promotion and strive for a process that is grounded in efficiency, transparency and collaboration for our internal candidates. Open positions are posted, and employees are highly encouraged to apply for promotion within the organization. In 2025, more than 7% of our employees were promoted to elevated roles within our organization.

Compensation & Benefits

We designed our compensation program with the goal of providing a balanced and effective way of ensuring internal equity and market competitiveness in our pay practices. We have coupled external market-driven data with a comprehensive performance review assessment tool to strike the balance that best represents our compensation strategy and links pay to performance. On an annual basis, our Human Resources department evaluates market compensation ranges for each position to ensure we are appropriately compensating our employees. We believe this total rewards program directly aligns with our compensation and benefits strategy.

Our employee benefit programs are thoughtfully designed to meet the needs of our workforce by offering comprehensive and competitive programs to support our employees and their families. These programs provide flexibility and choice in coverage, valuable resources to protect and enhance financial security, and benefits that help balance work and personal life. Some of the benefits that we offer our employees include:

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• health (including telehealth), dental and vision insurance,

• employer-subsidized health savings account,

• a 401(k) plan with a generous company matching contribution,

• an employee stock purchase plan that allows employees to purchase our common stock at a discount,

• health care and dependent care flexible spending accounts,

• income protection through our sick pay, salary continuation, long-term disability policies and life insurance and AD&D insurance,

• business travel accident insurance,

• a scholarship program for the children of non-officer employees,

• tuition reimbursement,

• a commuter subsidy to encourage and support the use of public transportation,

• paid vacation, holiday, personal days, a volunteer day program, and paid parental leave to balance work and personal life,

• wellness and mental health well-being programs,

• employee assistance program,

• matching charitable gift program,

• back-up care for children and elders, and

• pet insurance.

Health, Safety & Wellness

As one of the largest publicly traded premier workplace REITs (based on total market capitalization as of December 31, 2025) in the United States, we appreciate the influence of buildings on human health and its importance to our clients and employees. The health, safety and security of our employees, clients, contractors and other visitors to our properties are our highest priority. We have implemented numerous operational measures to promote better health and safety in our buildings, including measures related to indoor air quality in our buildings.

We believe the success of our employees is dependent upon their overall well-being, including their physical health, mental health, work-life balance and financial well-being. In addition to the benefits outlined above, we also offer our employees an Employee Wellness Program, an Employee Assistance Program and a Mental Health Well-Being Program. The Employee Wellness Program was established in 2016 to encourage employees to improve their health and well-being by offering a variety of activities and engaging content to meet individual wellness goals. Qualifying program participants receive a discount on a portion of their health insurance cost. The Employee Assistance Program includes services for childcare, eldercare, personal or work-related relationships, financial planning assistance, stress management, mental health, general wellness and self-help. BXP also offers a premium mental health wellbeing program that provides online resources and support for employees facing a wide variety of issues.

Policies with Respect to Certain Activities

The discussion below sets forth certain additional information regarding our investment, financing and other policies. These policies have been determined by BXP’s Board of Directors and, in general, may be amended or revised from time to time by the Board of Directors.

Investment Policies

Investments in Real Estate or Interests in Real Estate

Our investment objectives are to provide quarterly cash dividends/distributions to our securityholders and to achieve long-term capital appreciation through increases in our value. We have not established a specific policy regarding the relative priority of these investment objectives.

We expect to continue to pursue our investment objectives primarily through the ownership of our current properties, development and redevelopment projects and other acquired properties. We currently intend to continue to invest primarily in developments of properties and acquisitions of existing improved properties or properties in

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need of redevelopment, and acquisitions of land that we believe have development potential, primarily in our existing markets of Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC. We have explored and may continue to explore for future investment in select domestic and international markets that exhibit these same traits. Future investment or development activities will not be limited to a specified percentage of our assets. We intend to engage in such future investment or development activities in a manner that is consistent with the maintenance of BXP’s status as a REIT for federal income tax purposes. In addition, we may purchase or lease income-producing commercial and other types of properties for long-term investment, expand and improve the real estate presently owned or other properties purchased, or sell such real estate properties, in whole or in part, when circumstances warrant. We do not have a policy that restricts the amount or percentage of assets that will be invested in any specific property, however, our investments may be restricted by our debt covenants.

We may also continue to participate with third parties in property ownership, through joint ventures or other types of co-ownership. These investments may permit us to own interests in larger assets without unduly restricting diversification and, therefore, add flexibility in structuring our portfolio.

Equity investments may be subject to existing mortgage financing and other indebtedness or such financing or indebtedness as may be incurred in connection with acquiring or refinancing these investments. Debt service on such financing or indebtedness will have a priority over any distributions with respect to BXP’s common stock. Investments are also subject to our policy not to be treated as an investment company under the Investment Company Act of 1940, as amended (the “1940 Act”).

Investments in Real Estate Mortgages and Mezzanine Debt

While our current portfolio consists primarily of, and our business objectives emphasize, equity investments in commercial real estate, we may, at the discretion of the Board of Directors of BXP, invest in mortgages and other types of real estate interests consistent with BXP’s qualification as a REIT. Investments in real estate mortgages run the risk that one or more borrowers may default under the mortgages and that the collateral securing such mortgages may not be sufficient to enable us to recoup our full investment. We may invest in participating, convertible or traditional mortgages if we conclude that we may benefit from the cash flow, or any appreciation in value of the property or as an entrance to the fee ownership. As of December 31, 2025, we had one note receivable and two related-party note receivables outstanding, which totaled approximately $37.7 million, after adjustments for financing costs and the current expected credit loss allowance.

Securities of or Interests in Entities Primarily Engaged in Real Estate Activities

Subject to the percentage of ownership limitations and gross income and asset tests necessary for BXP’s REIT qualification and our debt covenants, we also may invest in securities of other REITs, other entities engaged in real estate activities or securities of other issuers, including for the purpose of exercising control over such entities.

Dispositions

Our long-term business strategy includes selective asset sales from time to time. In general, we decide to dispose or partially dispose of properties based upon a periodic review of our portfolio and the determination by the Board of Directors of BXP that doing so is in our best interests. However, a key component of our current strategic action plan introduced at our September 2025 Investor Day is the execution of a multi-year asset sales program to generate approximately $1.9 billion in net proceeds to fund our development pipeline and reduce leverage. See “ Liquidity and Capital Resources” within “Item 7—Management’s Discussion and Analysis of Financial Condition and Results of Operations” for more details on our asset sales program.

Any decision to dispose of a property or a partial interest in a property will be authorized by the Board of Directors of BXP or a committee thereof. Some holders of limited partnership interests in BPLP could incur adverse tax consequences upon the sale of certain of our properties that differ from the tax consequences to BXP. Consequently, holders of limited partnership interests in BPLP may have different objectives regarding the appropriate pricing and timing of any such sale. Such different tax treatment derives in most cases from the fact that we acquired these properties in exchange for partnership interests in contribution transactions structured to allow the prior owners to defer taxable gain. Generally, this deferral continues so long as we do not dispose of the properties in a taxable transaction. Unless a sale by us of these properties is structured as a like-kind exchange under Section 1031 of the Internal Revenue Code of 1986, as amended (the “Code”), or in a manner that otherwise allows deferral to continue, recognition of the deferred tax gain allocable to these prior owners is generally triggered by a sale. As of December 31, 2025, we had one property that was subject to a tax protection agreement, which may limit our ability to dispose of the asset or require us to pay damages to the prior owner in the event of a taxable

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sale in violation of the agreement. The tax protection agreement expires on December 14, 2033, or earlier upon the occurrence of certain events.

Financing Policies

The agreement of limited partnership of BPLP and BXP’s certificate of incorporation and bylaws do not limit the amount or percentage of indebtedness that we may incur. Further, we do not have a policy limiting the amount of indebtedness that we may incur, nor have we established any limit on the number or amount of mortgages that may be placed on any single property or on our portfolio as a whole. However, our mortgages, credit facilities, joint venture agreements and unsecured debt securities contain customary restrictions, requirements and other limitations on our ability to incur indebtedness. In addition, we evaluate the impact of incremental leverage on our debt metrics and the credit ratings of BPLP’s publicly traded debt. A reduction in BPLP’s credit ratings could result in us borrowing money at higher interest rates.

The Board of Directors of BXP will consider a number of factors when evaluating our level of indebtedness and when making decisions regarding the incurrence of indebtedness, including the purchase price of properties to be acquired with debt financing, the estimated market value of our properties upon refinancing, the cost and effectiveness of entering into interest rate swaps, caps, floors and other interest rate hedging contracts and the ability of particular properties, and us as a whole, to generate cash flow to cover expected debt service.

Policies with Respect to Other Activities

As the sole general partner of BPLP, BXP has the authority to issue additional common and preferred units of limited partnership interest of BPLP. BXP has issued, and may in the future issue, common or preferred units of limited partnership interest to persons who contribute their direct or indirect interests in properties to us in exchange for such common or preferred units. We have not engaged in trading, underwriting or agency distribution or sale of securities of issuers other than BXP and BPLP does not intend to do so. At all times, we intend to make investments in such a manner as to enable BXP to maintain its qualification as a REIT, unless, due to changes in circumstances or to the Code, the Board of Directors of BXP determines that it is no longer in the best interest of BXP to qualify as a REIT. We may make loans to third parties, including, without limitation, to joint ventures in which we participate or in connection with the disposition of a property. We intend to make investments in such a way that we will not be treated as an investment company under the 1940 Act. Our policies with respect to these and other activities may be reviewed and modified or amended from time to time by the Board of Directors of BXP.

Governmental Regulations

General

Compliance with various governmental regulations has an impact on our business, including our capital expenditures, earnings and competitive position, which can be material. We incur costs to monitor and take actions to comply with governmental regulations that are applicable to our business, which include, among others, (1) federal securities laws and regulations, (2) applicable stock exchange requirements, and (3) federal, state and local laws and regulations related to (a) our status as a REIT and other tax laws and regulations, and (b) real property, the improvements thereon and the operation thereof, such as laws and regulations relating to the environment, health and safety, zoning, usage, building, fire and life safety codes, (4) the requirements of the Office of Foreign Assets Control of the United States Department of the Treasury and (5) the Americans with Disabilities Act of 1990. In addition to the discussion below, see “ Item 1A. – Risk Factors ” for a discussion of these governmental regulations and other material risks to us, including, to the extent material, to our competitive position, and see “ Item 7— Management’s Discussion and Analysis of Financial Condition and Results of Operations ” together with our consolidated financial statements, including the related notes included therein, for a discussion of material information relevant to an assessment of our financial condition and results of operations, including, to the extent material, the effects that compliance with governmental regulations may have upon our capital expenditures and earnings.

Environmental Matters

It is our policy to retain independent environmental consultants to conduct or update Phase I environmental assessments (which generally do not involve invasive techniques such as soil or ground water sampling) and asbestos surveys in connection with our acquisition of properties. These pre-purchase environmental assessments have not revealed environmental conditions that we believe will have a material adverse effect on our business, assets, financial condition, results of operations or liquidity, and we are not otherwise aware of environmental

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conditions with respect to our properties that we believe would have such a material adverse effect. However, from time to time environmental conditions at our properties have required and may in the future require environmental testing and/or regulatory filings, as well as remedial action.

For example, in February 1999, we (through a joint venture) acquired from Exxon Corporation a property in Massachusetts that was formerly used as a petroleum bulk storage and distribution facility and was known by the state regulatory authority to contain soil and groundwater contamination. We developed an office park on the property. We engaged a specially licensed environmental consultant to oversee the management of contaminated soil and groundwater that was disturbed in the course of construction. Under the property acquisition agreement, Exxon agreed to (1) bear the liability arising from releases or discharges of oil and hazardous substances which occurred at the site prior to our ownership, (2) continue monitoring and/or remediating such releases and discharges as necessary and appropriate to comply with applicable requirements, and (3) indemnify us for certain losses arising from preexisting site conditions. Any indemnity claim may be subject to various defenses and contractual limitations, including time limits and limits on the specific use of the property, and there can be no assurance that the amounts paid under the indemnity, if any, would be sufficient to cover the liabilities arising from any such releases and discharges.

Environmental investigations at some of our properties and certain properties owned by our affiliates have identified groundwater contamination migrating from off-site source properties. In each case we engaged a licensed environmental consultant to perform the necessary investigations and assessments, and to prepare any required submittals to the regulatory authorities. In each case the environmental consultant concluded that the properties qualify under the regulatory program or the regulatory practice for a status which eliminates certain deadlines for conducting response actions at a site. We also believe that these properties qualify for liability relief under certain statutory provisions or regulatory practices regarding upgradient releases. Although we believe that the current or former owners of the upgradient source properties may bear responsibility for some or all of the costs of addressing the identified groundwater contamination, we will take such further response actions (if any) that we deem necessary or advisable. Other than periodic testing at some of these properties, no such additional response actions are anticipated at this time.

Some of our properties and certain properties owned by our affiliates are located in urban, industrial and other previously developed areas where fill or current or historical use of the areas have caused site contamination. Accordingly, it is sometimes necessary to institute special soil and/or groundwater handling procedures and/or include particular building design features in connection with development, construction and other property operations in order to achieve regulatory closure and/or ensure that contaminated materials are addressed in an appropriate manner. In these situations, it is our practice to investigate the nature and extent of detected contamination, including potential issues associated with vapor intrusion concerns and/or potential contaminant migration to or from the subject property in ground water, assess potential liability risks and estimate the costs of required response actions and special handling procedures. We then use this information as part of our decision-making process with respect to the acquisition, deal structure and/or development of the property. For example, we own a parcel in Massachusetts which was formerly used as a quarry/asphalt batching facility. Pre-purchase testing indicated that the site contained relatively low levels of certain contaminants. We have developed an office park on this property. Prior to and during redevelopment activities, we engaged a specially licensed environmental consultant to monitor environmental conditions at the site and prepare necessary regulatory submittals based on the results of an environmental risk characterization. A submittal has been made to the regulatory authorities in order to achieve regulatory closure at this site. The submittal included an environmental deed restriction that mandates compliance with certain protective measures in a portion of the site where low levels of residual soil contamination have been left in place in accordance with applicable laws.

We expect that resolution of the environmental matters described above will not have a material impact on our business, assets, financial condition, results of operations or liquidity. However, we cannot assure you that we have identified all environmental liabilities at our properties, that all necessary remediation actions have been or will be undertaken at our properties, that we will be indemnified, in full or at all, or that we will have insurance coverage in the event that such environmental liabilities arise.

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Corporate Governance

BXP is currently governed by an eleven-member Board of Directors. The current members of the Board of Directors of BXP are Bruce W. Duncan, Diane J. Hoskins, Mary E. Kipp, Joel I. Klein, Douglas T. Linde, Matthew J. Lustig, Timothy J. Naughton, Julie G. Richardson, Owen D. Thomas, William H. Walton III, and Derek A. (Tony) West. All directors of BXP’s Board of Directors stand for election for one-year terms expiring at the next succeeding annual meeting of stockholders.

Owen D. Thomas currently serves as the Chairman of BXP’s Board of Directors and Joel I. Klein serves as its Lead Independent Director. The Board of Directors of BXP also has Audit, Compensation, Nominating and Corporate Governance and Sustainability Committees. The membership of each of these committees is set forth below.

Audit

Compensation

Nominating and

Corporate Governance

Sustainability

Bruce W. Duncan

Diane J. Hoskins

Mary E. Kipp

Joel I. Klein (2)

Douglas T. Linde

Matthew J. Lustig

Timothy J. Naughton

Julie G. Richardson

Owen D. Thomas (3)

William H. Walton III

Derek A. (Tony) West

X=Committee member, (1)=Committee Chair, (2)=Lead Independent Director, (3)=Chairman of BXP’s Board of Directors

BXP has the following corporate governance documents and procedures in place:

• The Board of Directors has adopted charters for each of its Audit, Compensation and Nominating and Corporate Governance Committees. A copy of each of these charters is available on our website at http://www.bxp.com under the heading “Investors” and subheading “Governance.”

• The Board of Directors has adopted Corporate Governance Guidelines, a copy of which is available on our website at http://www.bxp.com under the heading “Investors” and subheading “Governance” with the n ame “Governance Guidelines.”

• The Board of Directors has adopted a Code of Business Conduct and Ethics, which governs business decisions made and actions taken by BXP’s directors, officers and employees. A copy of this code is available on our website at http://www.bxp.com under the heading “Investors” and subheading “Governance” with the n ame “Code of Business Conduct and Ethics.” BXP intends to disclose on this website any amendment to, or waiver of, any provisions of this Code applicable to the directors and executive officers of BXP that would otherwise be required to be disclosed under the rules of the SEC or the New York Stock Exchange.

• The Board of Directors has established an ethics reporting system that employees may use to anonymously report possible violations of the Code of Business Conduct and Ethics, including concerns regarding questionable accounting, internal accounting controls or auditing matters, by telephone or over the internet.

• The Board of Directors has adopted a Policy on Political Spending, a copy of which is available on our website at http://www.bxp.com under the heading “Investors” and the subheading “Governance” with the name “Policy on Political Spending.” We disclose all political spending on our website and update such disclosures biannually.

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Competition

We compete in the leasing of premier workplace, retail and residential space with a considerable number of other real estate companies, some of which may have greater marketing and financial resources than are available to us. In addition, our hotel property competes for guests with other hotels, some of which may have greater marketing and financial resources than are available to us and to the manager of our one hotel, Marriott International, Inc.

Principal factors of competition in our primary business of owning, acquiring and developing premier workplaces are the quality of properties, leasing terms (including rent and other charges and allowances for tenant improvements), attractiveness and convenience of location, the quality and breadth of client services and amenities provided, and reputation as an owner and operator of premier workplaces in the relevant market. Additionally, our ability to compete depends upon, among other factors, trends in the national and local economies, investment alternatives, financial condition and operating results of current and prospective clients, availability and cost of capital, construction and renovation costs, taxes, utilities, governmental regulations, legislation and population trends.

In addition, at December 31, 2025, we had seven residential properties (including three under construction) and may in the future decide to acquire or develop additional residential properties. As an owner, we will also face competition for prospective residents from other operators/owners whose properties may be perceived to offer a better location or better amenities or whose rent may be perceived as a better value given the quality, location and amenities that the resident seeks. We will also compete against condominiums and single-family homes that are for sale or rent. Because the scale of our residential portfolio is relatively small, we expect to continue to retain third parties to manage our residential properties.

Our Hotel Property

We operate our hotel property through a taxable REIT subsidiary. The taxable REIT subsidiary, a wholly-owned subsidiary of BPLP, is the lessee pursuant to a lease for the hotel property. As lessor, BPLP is entitled to a percentage of gross receipts from the hotel property. The hotel lease is intended to provide the economic benefits of ownership of the underlying real estate to flow to us as rental income, while our taxable REIT subsidiary earns the profit or loss from operating the property as a hotel. Marriott International, Inc. continues to manage the hotel property under the Marriott name and under terms of the existing management agreements. Marriott has been engaged under a separate long-term incentive management agreement to operate and manage the hotel on behalf of the taxable REIT subsidiary.

Supplemental United States Federal Income Tax Considerations

The following discussion supplements and updates the disclosures under the heading “United States Federal Income Tax Considerations” in the prospectus dated May 17, 2023, contained in our Registration Statements on Form S-3 (File Nos. 333-272012, 333-272012-01) filed with the Securities and Exchange Commission on May 17, 2023 (the “Existing Tax Disclosure”). Capitalized terms herein that are not otherwise defined shall have the same meaning as when used in the Existing Tax Disclosure.

On July 4, 2025, the One Big Beautiful Bill Act (the “OBBB”), was enacted. The OBBB makes major changes to the Code, including some provisions of the Code that affect the taxation of REITs and their investors. In particular,

• For taxable years beginning on or after January 1, 2026, the OBBB relaxed the REIT asset test requirement with respect to taxable REIT subsidiaries, providing that not more than 25% (relaxed from 20%) of the gross value of a REIT’s assets may be represented by securities of one or more taxable REIT subsidiaries.

• The OBBB permanently extended the pass-through qualified business income deduction, generally allowing individuals to deduct 20% of the aggregate amount of ordinary REIT dividends distributed by a REIT. This deduction was due to expire for tax years beginning after December 31, 2025.

• The OBBB provides that the highest individual marginal tax rate will not revert from 37% to 39.6% for taxable years beginning after December 31, 2025. The 37% rate is made permanent.

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To the extent the information set forth in the Existing Tax Disclosure is inconsistent with this supplemental information, this supplemental information supersedes the information in the Existing Tax Disclosure. This supplemental information is provided on the same basis and subject to the same qualifications as are set forth in the first four paragraphs of the Existing Tax Disclosure as if those paragraphs were set forth in this Annual Report on Form 10-K.

Item 1A. Risk Factors.

Set forth below are the risks that we believe are material to our investors and they should be carefully considered. Throughout this section, we refer to the equity and debt securities of both BXP and BPLP as our “securities,” and the investors who own securities of BXP, BPLP or both, as our “securityholders.” These risks are not all of the risks we face and other factors not presently known to us or that we currently believe are immaterial may also affect our business if they occur. This section contains forward-looking statements. You should refer to the explanation of the qualifications and limitations on forward-looking statements beginning on page 52 .

Risks Related to Our Business and Operations

Our performance depends upon the economic conditions, particularly the supply and demand characteristics, of our markets—Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC.

Substantially all of our revenue is derived from properties located in six markets: Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC. A downturn in the economies of these markets, or the impact that a downturn in the overall national economy may have upon these economies, could result in reduced demand for office space and/or a reduction in rents. Because our portfolio consists primarily of premier workplace buildings (as compared to a more diversified real estate portfolio), a decrease in demand for workplaces in turn could adversely affect our results of operations. Additionally, there are submarkets within our markets that are dependent upon a limited number of industries. For example, in our Washington, DC market, we focus on leasing our properties to governmental contractors and legal firms. In our West Coast markets, our leasing is focused on clients in the technology and media industries, as well as legal firms. In addition, in our New York market, we have historically leased properties to financial, legal and other professional firms. A reduction in spending by the Federal Government, sustained changes in space utilization due to remote work models and/or changes from workforce reductions due to artificial intelligence, and/or a significant downturn in one or more of the foregoing sectors have resulted in, and could continue to result in, reduced demand for office space and adversely affect our results of operations.

In addition, a significant economic downturn over a period of time could result in an event or change in circumstances that results in an impairment of a long-lived asset or an “other than temporary” impairment in the value of our investments in unconsolidated joint ventures. For the year ended December 31, 2025, BXP and BPLP recognized impairments of long-lived assets of approximately $85.8 million and $82.9 million, respectively, and one of our investments in an unconsolidated joint venture recognized an “other than temporary” impairment of approximately $145.1 million. For additional information on these impairments, see Notes 3 and 6 to the Consolidated Financial Statements. Any future impairments could have a material adverse effect on our results of operations in the period in which the charge is taken.

Market and economic volatility due to adverse economic and political conditions, health crises or dislocations in the credit markets could have a material adverse effect on our results of operations, financial condition and ability to pay dividends and/or distributions.

Our business may be adversely affected by market and economic volatility experienced by the U.S. and global economies, the real estate industry as a whole and/or the local economic conditions in the markets in which our properties are located. Such adverse economic and political conditions may include, among other issues, inflation, elevated interest rates, policy changes, prolonged labor market challenges impacting the recruitment and retention of talent, volatility in the public equity and debt markets, and international economic and other conditions, including pandemics, geopolitical instability and other conditions beyond our control. These current conditions, or similar conditions existing in the future, may adversely affect our results of operations, financial condition and ability to pay dividends and distributions as a result of the following, among other potential consequences:

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• federal policy changes, such as the implementation of tariffs that have resulted in, and may continue to result in, global supply chain disruptions and/or sustained inflation, could negatively impact interest rates, potential changes to U.S. federal tax laws and budgetary changes related to government leases;

• the financial condition of our clients may be adversely affected, which may result in client defaults under leases due to bankruptcy, lack of liquidity, lack of funding, operational failures or for other reasons;

• significant job losses and/or a sustained shift away from collective in-person work environments or relocations away from the markets in which we operate may occur, which could decrease overall demand for workplaces in the regions in which we operate and cause market rental rates and property values to be negatively impacted;

• our inability to borrow on terms and conditions that we find acceptable, or at all, which could reduce our ability to pursue acquisition and development opportunities and refinance existing debt, reduce our returns from our acquisition and development activities and increase our future interest expense;

• reduced values of our properties may limit our ability to dispose of assets at attractive prices or to obtain debt financing secured by our properties and may reduce the availability of unsecured loans;

• the value and liquidity of our short-term investments and cash deposits could be reduced as a result of a deterioration of the financial condition of the institutions that hold our cash deposits or the institutions or assets in which we have made short-term investments, a dislocation of the markets for our short-term investments, increased volatility in market rates for such investments or other factors;

• one or more lenders under our line of credit could refuse to fund their financing commitment to us or could fail, and we may not be able to replace the financing commitment of any such lenders on favorable terms, or at all; and

• one or more counterparties to our derivative financial instruments could default on their obligations to us, or could fail, increasing the risk that we may not realize the benefits of these instruments. For example, in connection with our offering of 2.00% Exchangeable Senior Notes due 2030 in September 2025, we entered into capped call transactions with certain option counterparties. The option counterparties are financial institutions, and we are subject to the risk that any or all of them might default under the capped call transactions. Our exposure to the credit risk of the option counterparties is not secured by any collateral. Further, global economic conditions have resulted in the actual or perceived failure or financial difficulties of certain financial institutions and could adversely impact the option counterparties’ performance under the capped call transactions. We can provide no assurances as to the financial stability or viability of the option counterparties.

Our success depends on key personnel whose continued service is not guaranteed.

We depend on the efforts of key personnel, particularly Owen D. Thomas, Chief Executive Officer, Douglas T. Linde, President and Michael E. LaBelle, Executive Vice President, Chief Financial Officer & Treasurer. Among the reasons that Messrs. Thomas, Linde and LaBelle are important to our success is that each has a national reputation, which attracts business and investment opportunities and assists us in negotiations with lenders, joint venture partners and other investors. If we lost their services, our relationships with lenders, potential clients and industry personnel could diminish.

Our Regional Managers also have strong reputations. Their reputations aid us in identifying opportunities, having opportunities brought to us, and negotiating with clients and build-to-suit prospects. While we believe that we could find replacements for these key personnel, the loss of their services could materially and adversely affect our operations because of diminished relationships with lenders, prospective clients and industry personnel.

Risks Related to Real Estate

Our performance and value are subject to risks associated with our real estate assets and with the real estate industry.

Our economic performance and the value of our real estate assets, and consequently the value of our securities, are subject to the risk that if our properties do not generate revenues sufficient to meet our operating expenses, including debt service and capital expenditures, our cash flow and ability to pay distributions to our

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securityholders will be adversely affected. The following factors, among others, may adversely affect the income generated by our properties:

• downturns in the national, regional and local economic conditions (particularly increases in unemployment);

• sustained changes in client preferences and space utilization from full-time, collective in-person work environments to hybrid or remote work models and/or changes from workforce reductions due to artificial intelligence, which could decrease overall demand for workplaces and negatively impact market rental rates and property values;

• competition from other office, life sciences, hotel, retail and residential buildings;

• local real estate market conditions, such as oversupply or reduction in demand for office, life sciences, hotel, retail or residential space;

• changes in interest rates and availability of financing;

• vacancies, changes in market rental rates and the need to periodically repair, renovate and re-let space;

• delays in completion of development and redevelopment projects due to supply chain disruptions and labor shortages;

• increased costs to maintain, renovate and develop our properties related to inflation;

• increased operating costs, including insurance expense, utilities, real estate taxes, state and local taxes and heightened security costs;

• civil disturbances, earthquakes and other natural disasters or terrorist acts or acts of war which may result in uninsured or underinsured losses or decrease the desirability of our properties to our clients in impacted locations;

• significant expenditures associated with each investment, such as debt service payments, real estate taxes (including reassessments and changes in tax laws), insurance and maintenance costs which are generally not reduced when circumstances cause a reduction in revenues from a property;

• declines in the financial condition of our clients and our ability to collect rents from our clients; and

• decreases in the underlying value of our real estate.

We face potential adverse effects from major clients’ bankruptcies or insolvencies.

The bankruptcy or insolvency of a major client may adversely affect the income produced by our properties. Our clients could file for bankruptcy protection or become insolvent in the future. We cannot evict a client solely because of its bankruptcy. On the other hand, a bankrupt client may reject and terminate its lease with us. In such case, our claim against the bankrupt client for unpaid and future rent would be subject to a statutory cap that might be substantially less than the remaining rent actually owed under the lease, and, even so, our claim for unpaid rent would likely not be paid in full. This shortfall could adversely affect our cash flow and results of operations.

Our properties face significant competition.

We face significant competition from developers, owners and managers of office, life sciences and residential properties and other commercial real estate, including sublease space available from our clients. Substantially all of our properties face competition from similar properties in the same market. This competition may affect our ability to attract and retain clients and may reduce the rents we are able to charge. These competing properties may have vacancy rates higher than our properties, which may result in their owners being willing to lease available space at lower rates than the space in our properties.

We face potential difficulties or delays renewing leases or re-leasing space.

We derive most of our income from rent received from our clients. If a client experiences a downturn in its business or other types of financial distress, it may be unable to make timely rental payments. Also, when our clients decide not to renew their leases, renew for less space or terminate early, we may not be able to re-let the space or there could be a substantial delay in re-letting the space. Even if clients decide to renew or lease new

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space, the terms of renewals or new leases, including the cost of required renovations or concessions to clients, may be less favorable to us than current lease terms. As a result, our cash flow could decrease and our ability to make distributions to our securityholders could be adversely affected.

Our actual costs to develop properties may exceed our budgeted costs.

We intend to continue to develop and substantially renovate office, life sciences, retail and residential properties. Our current and future development and construction activities may be exposed to the following risks:

• we may be unable to proceed with the development of properties because we cannot obtain financing on favorable terms or at all;

• we may incur construction costs for a development project that exceed our original estimates due to increased materials, labor, leasing or other costs, increases in interest rates, or supply chain disruptions, any of which could make completion of the project less profitable because market rents may not increase sufficiently to compensate for the increase in construction costs;

• we may be unable to obtain, or face delays in obtaining, required zoning, land-use, building, occupancy, and other governmental permits and authorizations, which could result in increased costs and could require us to abandon our activities entirely with respect to a project;

• we may abandon development opportunities after we begin to explore them and, as a result, we may lose deposits or fail to recover expenses already incurred;

• we may expend funds on and devote management’s time to projects that we do not complete;

• we may be unable to complete construction and/or leasing of a property on schedule or at all; and

• we may suspend development projects after construction has begun due to changes in economic conditions or other factors, and this may result in the write-off of costs, payment of additional costs or increases in overall costs when the development project is restarted.

Investment returns from our developed properties may be less than anticipated.

Our developed properties may be exposed to the following risks:

• we may lease developed properties at rental rates that are less than projected, or at a slower pace than projected, at the time we decide to undertake the development;

• operating expenses and construction costs may be greater than projected at the time of development, resulting in our investment being less profitable than we expected; and

• occupancy rates and rents at newly developed properties may fluctuate depending on a number of factors, including market and economic conditions, and may result in our investments being less profitable than we expected or not profitable at all.

We face risks associated with the development of mixed-use commercial and residential properties.

We operate, are currently developing, and may in the future develop, properties either alone or through joint ventures with other parties that are known as “mixed-use” properties. For mixed-use developments, this means that in addition to the development of office space, the project may also include space for residential, retail, hotel or other commercial purposes. We are also developing, and may in the future develop, residential buildings. We have less experience in developing and managing non-office and non-retail real estate than we do with office real estate. As a result, if a development project includes a non-office or non-retail use, we may seek to develop that component ourselves, sell the rights to that component to a third-party developer with experience in that use or we may seek to partner with such a developer. If we do not sell the rights or partner with such a developer, or if we choose to develop the other component ourselves, we would be exposed not only to those risks typically associated with the development of commercial real estate generally, but also to specific risks associated with the development and ownership of non-office and non-retail real estate. In addition, even if we sell the rights to develop the other component or elect to participate in the development through a joint venture, we may be exposed to the risks associated with the failure of the other party to complete the development as expected. These include the risk that the other party would default on its obligations necessitating that we complete the other component ourselves (including providing any necessary financing). In the case of residential properties, these risks include competition

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for prospective residents from other operators whose properties may be perceived to offer a better location or better amenities or whose rent may be perceived as a better value given the quality, location and amenities that the resident seeks. We will also compete against condominiums and single-family homes that are for sale or rent. Because we have less experience with residential properties than with office and retail properties, we retain third parties to manage our residential properties. When we hire a third-party manager, we are dependent on them and their key personnel who provide services to us and we may not find a suitable replacement if the management agreement is terminated, or if key personnel leave or otherwise become unavailable to us.

Our use of joint ventures may limit our control over jointly owned investments and limit our flexibility to acquire other assets.

In appropriate circumstances, we intend to acquire and recapitalize or develop, as applicable, properties in joint ventures with other parties. We currently have joint ventures that are and are not consolidated within our financial statements. Our participation in joint ventures subjects us to risks, including but not limited to, the following risks that:

• our joint venture partners may have different objectives than we have regarding the appropriate timing and terms of any sale or refinancing of a property, its operation or, if applicable, the commencement of development activities, and a dispute with any of our joint venture partners could lead to the sale of a partner’s ownership interest in the venture or the property at a time or price that we do not find attractive;

• some of our joint ventures are subject to debt and, depending on credit market conditions, the refinancing of such debt may require equity capital calls;

• our joint venture partners may be structured differently than us for tax purposes and this could create conflicts of interest, including with respect to our compliance with the REIT requirements, and our REIT status could be jeopardized if any of our joint ventures do not operate in compliance with REIT requirements;

• our joint venture partners may have competing interests in our markets that could create conflicts of interest;

• our joint venture partners may default on their obligations, which could necessitate that we fulfill their obligations ourselves;

• our joint ventures may be unable to repay any amounts that we may loan to them;

• our joint venture agreements may contain provisions limiting the liquidity of our interest for sale or sale of the entire asset;

• as the general partner or managing member of a joint venture, we could be generally liable under applicable law for the debts and obligations of the venture, and we may not be entitled to contribution or indemnification from our partners;

• our joint venture agreements may contain provisions that allow our partners to remove us as the general partner or managing member for cause, and this could result in liability for us to our partners under the governing agreement of the joint venture; and

• we may need our partner(s)’ approval to take certain actions and, therefore, we may be unable to cause a joint venture to implement decisions that we consider advisable.

We face the risk that third parties will not be able to service or repay loans we make to them.

From time to time, we have loaned and in the future may loan funds to (1) a third-party buyer to facilitate the sale of an asset by us to such third party, or (2) a third party in connection with the formation of a joint venture to acquire and/or develop a property. Making these loans subjects us to the following risks, each of which could have a material adverse effect on our cash flow, results of operations and/or financial condition:

• the third party may be unable to make full and timely payments of interest and principal on the loan when due;

• if the third-party buyer to whom we provide seller financing does not manage the property well, or the property otherwise fails to meet financial projections, performs poorly or declines in value, then the buyer

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may not have the funds or ability to raise new debt with which to make required payments of interest and principal to us;

• if we loan funds to a joint venture, and the joint venture is unable to make required payments of interest or principal, or both, or there are disagreements with respect to the repayment of the loan or other matters, then we could have a resulting dispute with our partner(s), and such a dispute could harm our relationship(s) with our partner(s) and cause delays in developing or selling the property or the failure to properly manage the property; and

• if we loan funds to a joint venture and the joint venture is unable to make required payments of interest and principal, or both, then we may exercise remedies available to us in the joint venture agreement that could allow us to increase our ownership interest or our control over major decisions, or both, which could result in an unconsolidated joint venture becoming consolidated with our financial statement; doing so could require us to reallocate the purchase price among the various asset and liability components and this could result in material changes to our reported results of operations and financial condition.

We face risks associated with property acquisitions.

We have acquired in the past and intend to continue to pursue the acquisition of properties and portfolios of properties, including large portfolios that could increase our size and result in alterations to our capital structure. Our acquisition activities and their success are subject to the following risks:

• even if we enter into an acquisition agreement for a property, we may be unable to complete that acquisition after making a non-refundable deposit and incurring certain other acquisition-related costs;

• we may be unable to obtain or assume financing for acquisitions on favorable terms or at all;

• acquired properties may fail to perform as expected;

• the actual costs of repositioning, redeveloping or maintaining acquired properties may be greater than our estimates;

• the acquisition agreement will likely contain conditions to closing, including completion of due diligence investigations to our satisfaction or other conditions that are not within our control, which may not be satisfied;

• acquired properties may be located in new markets, either within or outside the United States, where we may face risks associated with a lack of market knowledge or understanding of the local economy, lack of business relationships in the area, costs associated with opening a new regional office and unfamiliarity with local governmental and permitting procedures;

• we may acquire real estate through the acquisition of the ownership entity subjecting us to the risks of that entity; and

• we may be unable to quickly and efficiently integrate new acquisitions, particularly acquisitions of portfolios of properties, into our existing operations, and this could have an adverse effect on our results of operations and financial condition.

We have acquired in the past and in the future may acquire properties through the acquisition of first mortgage or mezzanine debt. Investments in these loans must be carefully structured to ensure that BXP continues to satisfy the various asset and income requirements applicable to REITs. If we fail to properly structure any such acquisition, BXP could fail to qualify as a REIT. In addition, acquisitions of first mortgage or mezzanine loans subject us to the risks associated with the borrower’s default, including potential bankruptcy, and there may be significant delays and costs associated with the process of foreclosure on collateral securing or supporting these investments.  There can be no assurance that we would recover any or all of our investment in the event of such a default or bankruptcy.

We have acquired in the past and in the future may acquire properties or portfolios of properties through tax deferred contribution transactions in exchange for partnership interests in BPLP. Among other things, this acquisition structure has the effect of reducing the amount of tax depreciation we can deduct over the tax life of the acquired properties, and it typically requires that we agree to protect the contributors’ ability to defer recognition of taxable gain through restrictions on our ability to dispose of the acquired properties and/or the allocation of partnership debt to the contributors to maintain their tax bases. These restrictions could limit our ability to sell an asset at a time, or on terms, that would be favorable absent such restrictions.

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Acquired properties may expose us to unknown liability.

We may acquire properties or invest in joint ventures that own properties subject to liabilities and without any recourse, or with only limited recourse, against the prior owners or other third parties with respect to unknown liabilities. As a result, if a liability were asserted against us based upon ownership of those properties, we might have to pay substantial sums to settle or contest it, which could adversely affect our results of operations and cash flow. Unknown liabilities with respect to acquired properties might include:

• liabilities for clean-up of undisclosed environmental contamination;

• claims by clients, vendors or other persons against the former owners of the properties;

• liabilities incurred in the ordinary course of business; and

• claims for indemnification by general partners, directors, officers and others indemnified by the former owners of the properties.

Competition for acquisitions may result in increased prices for properties.

We plan to continue to acquire properties as we are presented with attractive opportunities. We may face competition for acquisition opportunities with other investors, and this competition may adversely affect us by subjecting us to the following risks:

• we may be unable to acquire a desired property because of competition from other well-capitalized real estate investors, including publicly traded and private REITs, institutional investment funds and other real estate investors; and

• even if we are able to acquire a desired property, competition from other real estate investors may significantly increase the purchase price.

We may have difficulty selling our properties, which may limit our flexibility.

Properties like the ones that we own could be difficult to sell due to adverse economic conditions, a lack of available buyers and other conditions outside of our control. This may limit our ability to change our portfolio promptly in response to changes in economic or other conditions or to execute on our multi-year asset sales program. Any such inability to dispose of certain assets on the timelines we anticipate or on terms that are favorable to us, or at all, could negatively impact the proceeds we expect the multi-year asset sales program to generate, and accordingly, could adversely affect our financial condition and results of operations.

In addition, federal tax laws limit our ability to sell properties, which may affect our ability to sell properties without adversely affecting returns to our securityholders and our ability to dispose of certain of our properties is further constrained by their tax attributes. Properties that we developed and have owned for a significant period of time or that we acquired through tax deferred contribution transactions in exchange for partnership interests in BPLP often have low tax bases. Furthermore, as a REIT, BXP may be subject to a 100% “prohibited transactions” tax on the gain from dispositions of property if BXP is deemed to hold the property primarily for sale to customers in the ordinary course of business, unless the disposition qualifies under a safe harbor exception for properties that have been held for at least two years and with respect to which certain other requirements are met. The potential application of the prohibited transactions tax could cause us to forego potential dispositions of property or other opportunities that might otherwise be attractive to us, or to undertake such dispositions or other opportunities through a taxable REIT subsidiary, which would generally result in income taxes being incurred. If we dispose of these properties outright in taxable transactions, we may be required to distribute a significant amount of the taxable gain to our securityholders under the requirements of the Code applicable to REITs, which in turn would impact our future cash flow and may increase our leverage. In some cases, without incurring additional costs we may be restricted from disposing of properties contributed in exchange for our partnership interests under tax protection agreements with contributors. To dispose of low basis or taxprotected properties efficiently we from time to time use like-kind exchanges, which are intended to qualify for nonrecognition of taxable gain, but can be difficult to consummate and result in the property for which the disposed assets are exchanged inheriting their low tax bases and other tax attributes (including tax protection covenants).

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Because we own a hotel property, we face the risks associated with the hospitality industry.

The following factors, among others, are common to the hotel industry, and may reduce the receipts generated by our hotel property:

• our hotel property competes for guests with other hotels, a number of which may have greater marketing and financial resources than our hotel-operating business partners;

• if there is an increase in operating costs resulting from inflation and other factors, our hotel-operating business partners may not be able to offset such increase by increasing room rates;

• our hotel property is subject to the fluctuating and seasonal demands of business travelers and tourism; and

• our hotel property is subject to general and local economic and social conditions that may affect demand for travel in general, including fluctuations in consumer spending, public health concerns, war and terrorism.

In addition, because our hotel property is located in Cambridge, Massachusetts, it is subject to the Cambridge market’s fluctuations in demand, increases in operating costs and increased competition from additions in supply.

Failure to comply with Federal Government contractor requirements could result in substantial costs and loss of substantial revenue.

As of December 31, 2025, the U.S. Government was one of our clients and we are subject to compliance with a wide variety of complex legal requirements because we are a Federal Government contractor. These laws regulate how we conduct business, require us to administer various compliance programs and require us to impose compliance responsibilities on some of our contractors. Our failure to comply with these laws could subject us to fines, penalties and damages, cause us to be in default of our leases and other contracts with the Federal Government and bar us from entering into future leases and other contracts with the Federal Government. There can be no assurance that these costs and loss of revenue will not have a material adverse effect on our properties, operations or business.

Changes in rent control or rent stabilization and eviction laws and regulations in our markets could have a material adverse effect on our residential portfolio’s results of operations and residential property values.

Various state and local governments have enacted, and may continue to enact, rent control or rent stabilization laws and regulations or take other actions that could limit our ability to raise rents or charge certain fees, such as pet fees or application fees. Depending on the extent and terms of future enactments of rent control or rent stabilization laws and regulations, as well as any lawsuits against us arising from such issues, such future enactments could have a material adverse effect on our residential portfolio’s results of operations and the value of our residential properties.

State and local governments may also make changes to eviction and other tenants’ rights laws and regulations that could have a material adverse effect on our residential portfolio’s results of operations and the value of our residential properties. If we are restricted from re-leasing apartment units due to the inability to evict delinquent residents, our results of operations and property values for our residential properties may be adversely affected.

We did not obtain new owner’s title insurance policies in connection with properties acquired during BXP’s initial public offering.

We acquired many of our properties from our predecessors at the completion of BXP’s initial public offering in June 1997. Before we acquired these properties, each of them was insured by a title insurance policy. We did not obtain new owner’s title insurance policies in connection with the acquisition of these properties. To the extent we have financed properties after acquiring them in connection with the initial public offering, we have obtained new title insurance policies, however, the amount of these policies may be less than the current or future value of the applicable properties. Nevertheless, because in many instances we acquired these properties indirectly by acquiring ownership of the entity that owned the property and those owners remain in existence as our subsidiaries, some of these title insurance policies may continue to benefit us. Many of these title insurance policies may be for amounts less than the current or future values of the applicable properties. If there was a title defect related to any of these properties, or to any of the properties acquired at the time of the initial public offering of BXP, that is no

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longer covered by a title insurance policy, we could lose both our capital invested in and our anticipated profits from such property. We have obtained title insurance policies for all properties that we have acquired after the initial public offering of BXP, however, these policies may be for amounts less than the current or future values of the applicable properties.

Some potential losses are not covered by insurance.

Our property insurance program per occurrence limits are $1.0 billion for our portfolio insurance program, including coverage for acts of terrorism other than nuclear, biological, chemical or radiological terrorism (“Terrorism Coverage”). We also carry $1.35 billion of property insurance in excess of the $1.0 billion of coverage in our property insurance program for 601 Lexington Avenue, New York, New York, consisting of $750 million of property and Terrorism Coverage in excess of our property insurance program and $600 million of Terrorism Coverage only in excess of the $1.75 billion of coverage. Certain properties, including the General Motors Building located at 767 Fifth Avenue in New York, New York (“767 Fifth Avenue”), are currently insured in separate insurance programs. The property insurance program per occurrence limits for 767 Fifth Avenue are $1.625 billion, including Terrorism Coverage. We also currently carry nuclear, biological, chemical and radiological terrorism insurance coverage for acts of terrorism certified under the Federal Terrorism Risk Insurance Act (as amended, “TRIA”) (“NBCR Coverage”), which is provided by IXP, LLC (“IXP”) as a direct insurer, for the properties in our portfolio, including 767 Fifth Avenue, but excluding certain other properties owned in joint ventures with third parties or which we manage. The per occurrence limit for NBCR Coverage is $1.0 billion. Under TRIA, after the payment of the required deductible and coinsurance, the NBCR Coverage provided by IXP is backstopped by the Federal Government if the aggregate industry insured losses resulting from a certified act of terrorism exceed a “program trigger.” The program trigger is $200 million, the coinsurance is 20% and the deductible is 20% of the premiums earned by the insurer for the year prior to a claim. If the Federal Government pays out for a loss under TRIA, it is mandatory that the Federal Government recoup the full amount of the loss from insurers offering TRIA coverage after the payment of the loss pursuant to a formula in TRIA. We may elect to terminate the NBCR Coverage if the Federal Government seeks recoupment for losses paid under TRIA, if TRIA is not extended after its expiration on December 31, 2027, if there is a change in our portfolio or for any other reason. We intend to continue to monitor the scope, nature and cost of available terrorism insurance.

We also currently carry earthquake insurance on our properties located in areas known to be subject to earthquakes. Specifically, we currently carry earthquake insurance which covers our San Francisco and Los Angeles regions with a $330 million per occurrence limit, and a $330 million annual aggregate limit, $30 million of which is provided by IXP, as a direct insurer. This insurance is subject to a deductible in the amount of 5% of the value of the affected property. In addition, we currently carry earthquake insurance which covers our Seattle region with a $110 million per occurrence limit, and a $110 million annual aggregate limit. This insurance is subject to a deductible in the amount of 2% of the value of the affected property. The amount of our earthquake insurance coverage may not be sufficient to cover losses from earthquakes. In addition, the amount of earthquake coverage could impact our ability to finance properties subject to earthquake risk. We may discontinue earthquake insurance or change the structure of our earthquake insurance program on some or all of our properties in the future if the premiums exceed our estimation of the value of the coverage.

IXP, a captive insurance company which is a wholly-owned subsidiary, acts as a direct insurer with respect to a portion of our earthquake insurance coverage for our Greater San Francisco and Los Angeles properties and our NBCR Coverage. Insofar as we own IXP, we are responsible for its liquidity and capital resources, and the accounts of IXP are part of our consolidated financial statements. In particular, if a loss occurs which is covered by our NBCR Coverage but is less than the applicable program trigger under TRIA, IXP would be responsible for the full amount of the loss without any backstop by the Federal Government. IXP would also be responsible for any recoupment charges by the Federal Government in the event losses are paid out and its insurance policy is maintained after the payout by the Federal Government. If we experience a loss and IXP is required to pay under its insurance policy, we would ultimately record the loss to the extent of the required payment. Therefore, insurance coverage provided by IXP should not be considered as the equivalent of third-party insurance, but rather as a modified form of self-insurance. In addition, BPLP has issued a guarantee to cover liabilities of IXP in the amount of $20.0 million.

We continue to monitor the state of the insurance market in general, and the scope and costs of coverage for acts of terrorism, earthquakes, pandemics and cybersecurity incidents, in particular, but we cannot anticipate what coverage will be available on commercially reasonable terms in future policy years. There are other types of losses, such as from wars, for which we cannot obtain insurance at all or at a reasonable cost. With respect to such losses and losses from acts of terrorism, earthquakes, pandemics or other catastrophic events, if we experience a loss that

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is uninsured or that exceeds policy limits, we could lose the capital invested in the damaged properties, as well as the anticipated future revenues from those properties. Depending on the specific circumstances of each affected property, it is possible that we could be liable for mortgage indebtedness or other obligations related to the property. Any such loss could materially and adversely affect our business, financial condition and results of operations.

Actual or threatened terrorist attacks or other criminal acts may adversely affect our ability to generate revenues and the value of our properties.

We have significant investments in large metropolitan markets that have been, and may continue to be, the targets of actual or threatened terrorism attacks and other criminal acts, including Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC. As a result, some clients in these markets may (1) choose to relocate their businesses to other markets or to lower-profile office buildings within these markets that may be perceived to be less likely targets of future terrorist activity and/or (2) perceive a need for or request security enhancements . This could result in an overall decrease in the demand for office space in these markets generally or in our properties in particular, which could increase vacancies in our properties, necessitate that we lease our properties on less favorable terms or both, and/or increase our costs related to security, equipment and personnel. In addition, future terrorist attacks in these markets could directly or indirectly damage our properties, both physically and financially, or cause losses that materially exceed our insurance coverage. As a result of the foregoing, our ability to generate revenues and the value of our properties could decline materially. See also “ —Some potential losses are not covered by insurance. ”

We face risks associated with security breaches, incidents and compromises through cyber-attacks, cyber intrusions or otherwise, as well as other significant disruptions of our information technology (IT) networks and related systems.

We face risks associated with security breaches, incidents, and compromises, whether through cyber attacks or cyber intrusions over the internet, malware, computer viruses, attachments to e-mails, persons inside our organization or persons with access to systems inside our organization, social engineering tactics, and other significant disruptions of our IT networks and related systems. The risk of a security breach, incident, compromise, or disruption, particularly through cyber attack or cyber intrusion, including by computer hackers, foreign governments and cyber terrorists, has generally increased as the number, intensity and sophistication of attempted attacks and intrusions from around the world have increased. Our IT networks and related systems are essential to the operation of our business and our ability to perform day-to-day operations (including managing our building systems and accounting for our business operations) and, in some cases, may be critical to the operations of certain of our clients.

Although we make efforts to maintain the security and integrity of our IT networks and related systems, and we have implemented various measures designed to manage the risk of a security breach, incident, compromise or disruption, there can be no assurance that our security efforts and measures will be effective or that attempted security breaches, incident, compromise or disruptions would not be successful or damaging. Even the most well-protected information, networks, systems and facilities remain potentially vulnerable because the techniques used in such attempted security breaches evolve and generally are not recognized until launched against a target, and in some cases, are designed not to be detected and, in fact, may not be detected. Accordingly, we may be unable to anticipate these techniques or to implement adequate security barriers or other preventative measures, and thus it is impossible for us to entirely mitigate this risk.

Like other businesses, we have been, and expect to continue to be, subject to attempts at unauthorized access of our network, mishandling or misuse, computer viruses or malware, cyber attacks and intrusions and other events of varying degrees. To date, these events have not had, individually or in the aggregate, a material adverse effect on our operations or business. However, a security breach, incident, compromise or other significant disruption involving our IT networks and related systems could:

• disrupt the proper functioning of our networks and systems and therefore our operations and/or those of certain of our clients;

• result in misstated financial reports, violations of loan covenants, missed reporting deadlines and/or missed permitting deadlines;

• result in our inability to properly monitor our compliance with the rules and regulations regarding BXP’s qualification as a REIT;

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• result in the unauthorized access to, and destruction, loss, theft, misappropriation or release of, proprietary, confidential, sensitive or otherwise valuable information of ours or others, which others could use to compete against us or which could expose us to damage and claims or threats by third-parties for disruptive, destructive or otherwise harmful purposes and outcomes;

• result in our inability to maintain the building systems relied upon by our clients for the efficient use of their leased space;

• require significant management attention and resources to remedy any damages that result;

• subject us to claims for breach of contract, damages, credits, penalties or termination of leases or other agreements or subject us to litigation and regulatory investigations and related fines and penalties;

• be uninsured or exceed policy limits, increase operating costs, including insurance expenses, or make future cyber risk coverage unavailable on commercially reasonable terms ; and

• damage our reputation among our clients and investors generally.

Any one or more of the foregoing could have a material adverse effect on our results of operations, financial condition and cash flows. Refer to Part I, Item 1C. Cybersecurity in this Form 10-K for more information.

The use of technology based on artificial intelligence and machine learning presents risks and challenges that may adversely affect our business and results of operations.

We use artificial intelligence and machine learning technology (collectively, “AI”) capabilities with the goal of enhancing efficiencies in conducting our business. Our deployment and application of AI remains ongoing. While these AI tools hold promise in optimizing our work processes and driving efficiencies, their use, whether authorized or unauthorized, presents risks, challenges and unintended consequences that could adversely affect our business and results of operations or those of our clients. These include, but are not limited to:

• the release, leak or disclosure of proprietary, confidential, sensitive or otherwise valuable information as a result of or in connection with our use of AI tools;

• the incorporation of AI by our workforce (even when used in accordance with our guidelines) and our clients, vendors, contractors and other third-parties into their products or services, with or without our knowledge, in a manner that could give rise to allegations, legal claims and other issues pertaining to data privacy, information security, proprietary information and intellectual property considerations;

• the production of incomplete, inaccurate or otherwise flawed outputs, some of which may be difficult to detect, and the reliance on such outputs which could result in adverse consequences to us, including exposure to reputational and competitive harm, customer loss, legal liability, errors in our decision-making, process development or other business activities or otherwise have a negative impact on us; and

• the evolving legal regulations relating to AI, which may require significant resources to modify and maintain business practices to comply with applicable law or otherwise result in legal or regulatory action or create additional liabilities, the nature of which cannot be determined at this time.

We have implemented guidelines and policies specifically governing the use of AI tools in the workplace. Although we aim to use AI responsibly and securely and attempt to mitigate ethical and legal issues presented by its use, we may ultimately be unsuccessful in identifying or resolving issues before they arise. There can be no assurance that we will properly implement AI, and the failure to do so could have a material adverse effect on our results of operations or financial condition.

We face risks associated with our clients and contractual counterparties being designated “Prohibited Persons” by the Office of Foreign Assets Control.

Pursuant to Executive Order 13224 and other laws, the Office of Foreign Assets Control of the United States Department of the Treasury (“OFAC”) maintains a list of persons designated as terrorists or who are otherwise blocked or banned (“Prohibited Persons”). OFAC regulations and other laws prohibit conducting business or engaging in transactions with Prohibited Persons (the “OFAC Requirements”). Certain of our loan and other agreements require us to comply with OFAC Requirements. We have established a compliance program whereby

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clients and others with whom we conduct business are checked against the OFAC list of Prohibited Persons prior to entering into any agreement and on a periodic basis thereafter. Our leases and other agreements, in general, require the other party to comply with OFAC Requirements. If a client or other party with whom we contract is placed on the OFAC list we may be required by the OFAC Requirements to terminate the lease or other agreement. Any such termination could result in a loss of revenue or a damage claim by the other party that the termination was wrongful.

The outbreak of highly infectious or contagious diseases could adversely impact or cause disruption to our financial condition, results of operations, cash flows and liquidity and that of our clients.

Public health crises such as pandemics and similar outbreaks could adversely impact our business. The full extent to which any future pandemic or similar outbreak may impact our operations and those of our clients will depend on future developments, which are highly uncertain and cannot be predicted. Factors related to any public health crises that could have a material adverse effect on our results of operations and financial condition include:

• changes made by companies in response to a pandemic that could lead to a sustained shift away from collective in-person work environments or relocations away from the markets in which we operate, either of which could adversely affect the overall demand for workplaces in the regions in which we operate;

• reduced economic activity and/or supply chain disruptions or delays in delivery of products, services or other materials necessary for our clients that impact our clients’ businesses, financial condition or liquidity, may cause, one or more of our clients to be unable to meet their obligations to us, including their ability to make timely rental payments, in full or at all, or to otherwise seek modifications of such obligations, including rent concessions, deferrals or abatements, or to declare bankruptcy. Any one or more of the foregoing could:

• reduce our cash flows,

• adversely impact our ability to finance, refinance or sell a property,

• adversely impact our ability to continue paying distributions to our securityholders at current levels, or at all, and

• result in additional legal and other costs to enforce our rights, collect rent and/or re-lease the space occupied by the distressed client;

• the degree to which our clients’ businesses are negatively impacted could require us to write-off a client’s accrued rent balance and this could have a material adverse effect on our results of operations and liquidity;

• new laws, governmental policies, and similar actions, including legal restrictions on prosecutions, could adversely impact public safety and thereby adversely affect (1) the desirability of clients to lease space in our properties or markets, and (2) businesses’ office re-population plans;

• the impact of a pandemic could result in an event or change in circumstances that results in an impairment in the value of our properties or our investments in unconsolidated joint ventures, and any such impairment could have a material adverse effect on our results of operations in the periods in which the charge is taken;

• we may be unable to restructure or amend leases with certain of our clients on terms favorable to us or at all;

• the impact and validity of interpretations of lease provisions and applicable laws related to claims by clients regarding their obligations to pay rent as a result of a pandemic, and any adverse court rulings or decisions interpreting these provisions and laws, could have a material adverse effect on our results of operations and liquidity;

• the impact of governmental and business travel limitations and restrictions could result in temporary or sustained periods of decreased demand for stays at our hotel property;

• the extent of labor shortages, disruptions in the supply chains, inflation impacting costs of materials, delays in permitting or inspections, and other factors could result in our failure to meet the development milestones set forth in any applicable lease agreement, which could provide the client the right to terminate its lease or entitle the client to monetary damages, delay the commencement or completion of

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construction and our anticipated lease-up plans for a development/redevelopment project or our overall development pipeline, including recognizing revenue for new leases, that may cause returns on investment to be less than projected, and/or increase the costs of construction of new or existing projects, any of which could adversely affect our investment returns, profitability and/or our future growth; and

• the potential that business interruption, loss of rental income and/or other associated expenses related to our operations will not be covered in whole or in part by our insurance policies, which may increase unreimbursed liabilities.

We face risks associated with climate change and severe weather events, as well as the regulatory efforts intended to reduce the effects of climate change.

The physical effects of climate change could have a material adverse effect on our properties, operations and business. For example, many of our properties are located along the East and West coasts, particularly those in the central business districts of Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC. To the extent climate change causes changes in weather patterns, our markets could experience increases in storm intensity, extreme temperatures, rising sea-levels, extreme drought and/or wildfires. Over time, these conditions could result in declining demand for office space in our buildings or increased costs associated with infrastructure-related remediation projects. Climate change may also have indirect effects on our business by making property insurance unavailable or by increasing the cost of (i) property insurance on terms we find acceptable, (ii) real estate taxes or other assessments, (iii) energy and (iv) property maintenance. In addition, we face transition risks related to federal, state and local legislation and regulations that are being implemented, are under consideration to mitigate the effects of climate change or that require increased environmental disclosures and reporting. The costs of complying with evolving regulatory requirements, including GHG emissions regulations and policies, could negatively impact our financial results.

For additional discussion regarding our approach to climate resiliency and our continued commitment to transparent reporting of sustainability performance indicators, see “ Item 1. Business—Business and Growth Strategies—Sustainability ” and our annual Sustainability & Impact Report available on our website at http://www.bxp.com under the heading “Commitment.”

Potential liability for environmental contamination could result in substantial costs.

Under federal, state and local environmental laws, ordinances and regulations, we may be required to investigate and clean up the effects of releases of hazardous or toxic substances or petroleum products at or migrating from our properties simply because of our current or past ownership or operation of the real estate. If unidentified environmental problems arise, we may have to make substantial payments, which could adversely affect our cash flow and our ability to make distributions to our securityholders, because: as owner or operator we may have to pay for property damage and for investigation and clean-up costs incurred in connection with the contamination; the law typically imposes clean-up responsibility and liability regardless of whether the owner or operator knew of or caused the contamination; even if more than one person may be responsible for the contamination, each person who shares legal liability under the environmental laws may be held responsible for all of the clean-up costs; and governmental entities and third parties may sue the owner or operator of a contaminated site for damages and costs.

These costs could be substantial and in extreme cases could exceed the amount of our insurance or the value of the contaminated property. We currently carry environmental insurance in an amount and subject to deductibles that we believe are commercially reasonable. Specifically, we carry a pollution legal liability policy with a $20 million limit per incident and a policy aggregate limit of $40 million. The presence or migration of hazardous or toxic substances or petroleum products or the failure to properly remediate contamination may give rise to third-party claims for bodily injury, property damage and/or response costs and may materially and adversely affect our ability to borrow against, sell or rent an affected property. In addition, applicable environmental laws create liens on contaminated sites in favor of the government for damages and costs it incurs in connection with contamination. Changes in laws, regulations and practices and their implementation increasing the potential liability for environmental conditions existing at our properties, or increasing the restrictions on the handling, storage or discharge of hazardous or toxic substances or petroleum products or other actions may result in significant unanticipated expenditures.

Environmental laws also govern the presence, maintenance and removal of asbestos and other building materials. For example, laws require that owners or operators of buildings containing asbestos:

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• properly manage and maintain the asbestos;

• notify and train those who may come into contact with asbestos; and

• undertake special precautions, including removal or other abatement, if asbestos would be disturbed during renovation or demolition of a building.

Such laws may impose fines and penalties on building owners or operators who fail to comply with these requirements and may allow third parties to seek recovery from owners or operators for personal injury associated with exposure to asbestos fibers.

Some of our properties are located in urban and previously developed areas where fill or current or historic industrial uses of the areas have caused site contamination. It is our policy to retain independent environmental consultants to conduct or update Phase I environmental site assessments and asbestos surveys with respect to our acquisition of properties. These assessments generally include a visual inspection of the properties and the surrounding areas, an examination of current and historical uses of the properties and the surrounding areas and a review of relevant state, federal and historical documents, but do not involve invasive techniques such as soil and ground water sampling. Where appropriate, on a property-by-property basis, our practice is to have these consultants conduct additional testing, including sampling for asbestos, for lead and other contaminants in drinking water and, for soil and/or groundwater contamination where underground storage tanks are or were located or where other past site usage creates a potential environmental problem. Even though these environmental assessments are conducted, there is still the risk that:

• the environmental assessments and updates did not identify or properly address all potential environmental liabilities;

• a prior owner created a material environmental condition that is not known to us or the independent consultants preparing the assessments;

• new environmental liabilities have developed since the environmental assessments were conducted; and

• future uses or conditions such as changes in applicable environmental laws and regulations could result in environmental liability for us.

Inquiries about indoor air quality may necessitate special investigation and, depending on the results, remediation beyond our regular indoor air quality testing and maintenance programs. Indoor air quality issues can stem from inadequate ventilation, chemical contaminants from indoor or outdoor sources, and biological contaminants such as molds, pollen, viruses and bacteria. Indoor exposure to chemical or biological contaminants can be alleged to be connected to allergic reactions or other adverse health effects. If these conditions were to occur at one of our properties, we may be subject to third-party claims for personal injury, or may need to undertake a targeted remediation program, including without limitation, special cleaning measures and steps to increase indoor ventilation rates and eliminate sources of contaminants. Such remediation programs could be costly, necessitate the temporary relocation of some or all of the property’s clients or require rehabilitation of the affected property.

Compliance or failure to comply with the Americans with Disabilities Act or other safety regulations and requirements could result in substantial costs.

The Americans with Disabilities Act generally requires that certain buildings, including office buildings, residential buildings and hotels, be made accessible to disabled persons. Noncompliance could result in the imposition of fines by the federal government or the award of damages to private litigants. If, under the Americans with Disabilities Act, we are required to make substantial alterations and capital expenditures in one or more of our properties, including the removal of access barriers, it could adversely affect our financial condition and results of operations, as well as the amount of cash available for distribution to our securityholders.

Our properties are subject to various federal, state and local regulatory requirements, such as state and local fire and life safety requirements. If we fail to comply with these requirements, we could incur fines or private damage awards. We do not know whether existing requirements will change or whether compliance with future requirements will require significant unanticipated expenditures that will affect our cash flow and results of operations.

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Any future international activities will be subject to special risks and we may not be able to effectively manage our international business.

We have underwritten, and in the future may acquire, properties, portfolios of properties or interests in real estate-related entities on a strategic or selective basis in international markets that are new to us. If we acquire properties or platforms located in these markets, we will face risks associated with a lack of market knowledge and understanding of the local economy, forging new business relationships in the area and unfamiliarity with local laws and government and permitting procedures. In addition, our international operations will be subject to the usual risks of doing business abroad such as possible revisions in tax treaties or other laws and regulations, including those governing the taxation of our international income, restrictions on the transfer of funds and uncertainty over terrorist activities. We cannot predict the likelihood that any of these developments may occur. Further, we may in the future enter into agreements with non-U.S. entities that are governed by the laws of, and are subject to dispute resolution in the courts of, another country or region. We cannot accurately predict whether such a forum would provide us with an effective and efficient means of resolving disputes that may arise.

Investments in international markets may also subject us to risks associated with funding increasing headcount, integrating new offices, and establishing effective controls and procedures to regulate the operations of new offices and to monitor compliance with U.S. laws and regulations such as the Foreign Corrupt Practices Act and similar foreign laws and regulations, such as the U.K. Bribery Act.

We may be subject to risks from potential fluctuations in exchange rates between the U.S. dollar and the currencies of the other countries in which we invest.

If we invest in countries where the U.S. dollar is not the national currency, we will be subject to international currency risks from the potential fluctuations in exchange rates between the U.S. dollar and the currencies of those other countries. A significant depreciation in the value of the currency of one or more countries where we have a significant investment may materially affect our results of operations. We may attempt to mitigate any such effects by borrowing in the currency of the country in which we are investing and, under certain circumstances, by hedging exchange rate fluctuations; however, access to capital may be more restricted, or unavailable on favorable terms or at all, in certain locations. For leases denominated in international currencies, we may use derivative financial instruments to manage the international currency exchange risk. We cannot assure you, however, that our efforts will successfully neutralize all international currency risks.

Risks Related to Our Indebtedness and Financing

Our maturing debt bears interest at lower rates than the current market rates, which has increased, and may continue to increase our interest costs which could adversely impact our ability to refinance existing debt or sell assets on favorable terms or at all.

As of February 20, 2026, we had $2.3 billion outstanding indebtedness, excluding our unconsolidated joint ventures, that bears interest at a variable rate, and we may incur more indebtedness in the future. Approximately $0.9 billion of our variable rate debt has been hedged with interest rates swaps to fix SOFR for all, or a portion of the applicable debt term. As current interest rates remain higher than interest rates on our maturing debt, the interest costs on our debt have increased, which, if current rates are sustained or continue to increase, could adversely affect our cash flow and our ability to pay principal and interest on our debt and our ability to make distributions to our securityholders. Further, elevated interest rates could limit our ability to refinance existing debt when it matures or significantly increase our future interest expense. From time to time, we enter into interest rate swap agreements and other interest rate hedging contracts, including swaps, caps and floors. While these agreements are intended to lessen the impact of rising interest rates on us, they also expose us to the risk that the other parties to the agreements will not perform, we could incur significant costs associated with the settlement of the agreements, the agreements will be unenforceable and the underlying transactions will fail to qualify as highly-effective cash flow hedges under guidance included in ASC 815 “Derivatives and Hedging.” In addition, high interest rates could decrease the amounts third-parties are willing to pay for our assets, thereby limiting our ability to change our portfolio promptly in response to changes in economic or other conditions.

Covenants in our debt agreements could adversely affect our financial condition.

The mortgages on our properties contain customary covenants such as those that limit our ability, without the prior consent of the lender, to further mortgage the applicable property or to modify or discontinue insurance coverage. Our unsecured credit facility, unsecured debt securities and certain secured loans contain customary restrictions, requirements and other limitations on our ability to incur indebtedness, including total debt to asset

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ratios, secured debt to total asset ratios, debt service coverage ratios and minimum ratios of unencumbered assets to unsecured debt, which we must maintain. Our continued ability to borrow under our credit facilities is subject to compliance with our financial and other covenants. In addition, our failure to comply with such covenants could cause a default under the applicable debt agreement, and we may then be required to repay such debt with capital from other sources. Under those circumstances, other sources of capital may not be available to us, or be available only on unattractive terms. Additionally, in the future our ability to satisfy current or prospective lenders’ insurance requirements may be adversely affected if lenders generally insist upon greater insurance coverage against acts of terrorism or losses resulting from earthquakes than is available to us in the marketplace or on commercially reasonable terms.

We rely on debt financing, including borrowings under our unsecured credit facility, issuances of unsecured debt securities and debt secured by individual properties, to finance our existing portfolio, our acquisition and development activities and for working capital. If we are unable to obtain debt financing from these or other sources, or to refinance existing indebtedness upon maturity, our financial condition and results of operations would likely be adversely affected. If we breach covenants in our debt agreements, the lenders can declare a default and, if the debt is secured, can take possession of the property securing the defaulted loan. In addition, our unsecured debt agreements contain specific cross-default provisions with respect to specified other indebtedness, giving the unsecured lenders the right to declare a default if we are in default under other loans in some circumstances. Defaults under our debt agreements could materially and adversely affect our financial condition and results of operations.

We face risks associated with the use of debt to fund acquisitions and developments, including refinancing risk.

We are subject to the risks normally associated with debt financing, including the risk that our cash flow will be insufficient to meet required payments of principal and interest. We anticipate that only a small portion of the principal of our debt will be repaid prior to maturity. Therefore, we are likely to need to refinance at least a portion of our outstanding debt as it matures. There is a risk that we may not be able to refinance existing debt or that the terms of any refinancing will not be as favorable as the terms of our existing debt. If principal payments due at maturity cannot be refinanced, extended or repaid with proceeds from other sources, such as new equity capital, our cash flow may not be sufficient to repay all maturing debt in years when significant “balloon” payments come due. In addition, we may rely on debt to fund a portion of our new investments such as our acquisition and development activity. There is a risk that we may be unable to finance these activities on favorable terms or at all. These conditions, which increase the cost and reduce the availability of debt, may continue or worsen in the future.

We have had and may in the future have agreements with a number of limited partners of BPLP who contributed properties in exchange for partnership interests that require BPLP to maintain for specified periods of time secured debt on certain of our assets and/or allocate partnership debt to such limited partners to enable them to continue to defer recognition of their taxable gain with respect to the contributed property. These tax protection and debt allocation agreements may restrict our ability to repay or refinance debt. As of December 31, 2025, we had one tax protection agreement that could restrict our ability to repay or finance debt.

Our degree of leverage could limit our ability to obtain additional financing or affect the market price of our equity and debt securities.

As of February 20, 2026, our Consolidated Debt was approximately $15.6 billion (excluding unconsolidated joint venture debt).

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The following table presents Consolidated Market Capitalization and the corresponding ratios of Consolidated Debt to Consolidated Market Capitalization (dollars and shares / units in thousands):

February 20, 2026

Shares / Units Outstanding

Common Stock Equivalent

Equivalent Value (1)

Common Stock

Common Operating Partnership Units

Total Equity (A)

Consolidated Debt (B)

Consolidated Market Capitalization (A + B)

Consolidated Debt/Consolidated Market Capitalization [B / (A + B)]

(1) Values are based on the closing price per share of BXP’s Common Stock on February 20, 2026 of $60.88.

(2) Includes LTIP Units (including 2012 OPP Units and earned MYLTIP Units that were granted between 2013 - 2023), but excludes 2025 OPP Units and MYLTIP Units granted between 2024 and 2026 because the performance period for those awards has not yet ended.

Our degree of leverage could affect our ability to obtain additional financing for working capital, capital expenditures, acquisitions, development or other general corporate purposes. Our senior unsecured debt is currently rated investment grade by two major rating agencies. However, there can be no assurance that we will be able to maintain these ratings. In the event our senior debt is downgraded from its current ratings, we would likely incur higher borrowing costs and/or difficulty in obtaining additional financing. Our degree of leverage could also make us more vulnerable to a downturn in business or the economy generally. There is a risk that changes in our debt to market capitalization ratio, which is in part a function of BXP’s stock price, or BPLP’s ratio of indebtedness to other measures of asset value used by financial analysts may have an adverse effect on the market price of our equity or debt securities.

We face risks associated with short-term liquid investments.

We may invest cash balances in a variety of short-term investments that are intended to preserve principal value and maintain a high degree of liquidity while providing current income. From time to time, these investments may include (either directly or indirectly):

• direct obligations issued by the U.S. Treasury;

• obligations issued or guaranteed by the U.S. Government or its agencies;

• taxable municipal securities;

• obligations (including certificates of deposit) of banks and thrifts;

• commercial paper and other instruments consisting of short-term U.S. dollar denominated obligations issued by corporations and banks;

• repurchase agreements collateralized by corporate and asset-backed obligations;

• both registered and unregistered money market funds; and

• other highly rated short-term securities.

Investments in these securities and funds are not insured against loss of principal. Under certain circumstances we may be required to redeem all or part of our investment, and our right to redeem some or all of our investment may be delayed or suspended. In addition, there is no guarantee that our investments in these securities or funds will be redeemable at par value. A decline in the value of our investment or a delay or suspension of our right to redeem may have a material adverse effect on our results of operations or financial condition.

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Risks Related to Our Organization and Structure

Conflicts of interest exist with holders of interests in BPLP.

Sales of properties and repayment of related indebtedness will have different effects on holders of interests in BPLP than on BXP’s stockholders.

Some holders of interests in BPLP could incur adverse tax consequences upon the sale of certain of our properties and on the repayment of related debt which differ from the tax consequences to BXP and its stockholders. Consequently, these holders of partnership interests in BPLP may have different objectives regarding the appropriate pricing and timing of any such sale or repayment of debt. While BXP has exclusive authority under the limited partnership agreement of BPLP to determine when to refinance or repay debt or whether, when, and on what terms to sell a property, subject, in the case of certain properties, to the contractual commitments described below, any such decision would require the approval of BXP’s Board of Directors. While the Board of Directors has a policy with respect to these matters, directors and executive officers could exercise their influence in a manner inconsistent with the interests of some, or a majority, of BXP’s stockholders, including in a manner which could prevent completion of a sale of a property or the repayment of indebtedness.

Agreement not to sell some properties.

We have had and may have in the future agreements with the contributors of properties that we have acquired in exchange for partnership interests in BPLP pursuant to which we have agreed not to sell or otherwise transfer the properties, prior to specified dates, in any transaction that would trigger taxable income to the contributors. In addition, we are responsible for the reimbursement of certain tax-related costs to the prior owners if the subject properties are sold in a taxable sale. In general, our obligations to the prior owners are limited in time and only apply to actual damages suffered.

Also, BPLP has had and may have in the future agreements providing prior owners of properties with the right to guarantee specific amounts of indebtedness and, in the event that the specific indebtedness they guarantee is repaid or reduced, additional and/or substitute indebtedness. These agreements may hinder actions that BPLP may otherwise desire to take to repay or refinance guaranteed indebtedness because doing so would require BPLP to make payments to the prior owners if BPLP violates these agreements.

Limits on changes in control may discourage takeover attempts beneficial to stockholders.

Provisions in BXP’s charter and bylaws and the limited partnership agreement of BPLP, as well as provisions of the Code and Delaware corporate law, may:

• delay or prevent a change of control over BXP or a tender offer, even if such action might be beneficial to BXP’s stockholders; and

• limit BXP’s stockholders’ opportunity to receive a potential premium for their shares of common stock over then-prevailing market prices.

Stock Ownership Limit

To facilitate maintenance of BXP’s qualification as a REIT and to otherwise address concerns relating to concentration of stock ownership, BXP’s charter generally prohibits the ownership, directly, indirectly or beneficially, by any single stockholder of more than 6.6% of the number of outstanding shares of any class or series of its common stock. We refer to this limitation as the “ownership limit.” BXP’s Board of Directors may, in its sole discretion, waive or modify the ownership limit with respect to one or more persons if it is satisfied that ownership in excess of this limit will not jeopardize BXP’s status as a REIT for federal income tax purposes. In addition, under BXP’s charter, each of Mortimer B. Zuckerman and the respective families and affiliates of Mortimer B. Zuckerman and Edward H. Linde, as well as, in general, pension plans and mutual funds, may actually and beneficially own up to 15% of the number of outstanding shares of any class or series of BXP’s equity common stock. Shares owned in violation of the ownership limit will be subject to the loss of rights to distributions and voting and other penalties. The ownership limit may have the effect of inhibiting or impeding a change in control.

BPLP’s Partnership Agreement

BXP has agreed in the limited partnership agreement of BPLP not to engage in specified extraordinary transactions, including, among others, business combinations, unless limited partners of BPLP other than BXP receive, or have the opportunity to receive, either (1) the same consideration for their partnership interests as

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holders of BXP common stock in the transaction or (2) limited partnership units that, among other things, would entitle the holders, upon redemption of these units, to receive shares of common equity of a publicly traded company or the same consideration as holders of BXP common stock received in the transaction. If these limited partners would not receive such consideration, then we cannot engage in the transaction unless limited partners holding at least 75% of the common units of limited partnership interest, other than those held by BXP or its affiliates, consent to the transaction. In addition, BXP has agreed in the limited partnership agreement of BPLP that it will not complete specified extraordinary transactions, including among others, business combinations, in which BXP receives the approval of its common stockholders unless (1) limited partners holding at least 75% of the common units of limited partnership interest, other than those held by BXP or its affiliates, consent to the transaction or (2) the limited partners of BPLP are also allowed to vote and the transaction would have been approved had these limited partners been able to vote as common stockholders on the transaction. Therefore, if BXP’s common stockholders approve a specified extraordinary transaction, the partnership agreement requires the following before it can complete the transaction:

• holders of partnership interests in BPLP, including BXP, must vote on the matter;

• BXP must vote its partnership interests in the same proportion as its stockholders voted on the transaction; and

• the result of the vote of holders of partnership interests in BPLP must be such that had such vote been a vote of stockholders, the business combination would have been approved.

With respect to specified extraordinary transactions, BXP has agreed in BPLP’s partnership agreement to use its commercially reasonable efforts to structure such a transaction to avoid causing its limited partners to recognize gain for federal income tax purposes by virtue of the occurrence of or their participation in such a transaction.

As a result of these provisions, a potential acquirer may be deterred from making an acquisition proposal, and BXP may be prohibited by contract from engaging in a proposed extraordinary transaction, including a proposed business combination, even though BXP stockholders approve of the transaction.

We may change our policies without obtaining the approval of our stockholders.

Our operating and financial policies, including our policies with respect to acquisitions and dispositions of real estate, growth, operations, indebtedness, capitalization and dividends, are exclusively determined by BXP’s Board of Directors. Accordingly, our securityholders do not control these policies.

Risks Related to BXP’s Status as a REIT

Failure to qualify as a REIT would cause BXP to be taxed as a corporation, which would substantially reduce funds available for payment of dividends.

If BXP fails to qualify as a REIT for federal income tax purposes, it will be taxed as a corporation unless certain relief provisions apply. We believe that BXP is organized and qualified as a REIT and intends to operate in a manner that will allow BXP to continue to qualify as a REIT. However, we cannot assure you that BXP is qualified as such, or that it will remain qualified as such in the future. This is because qualification as a REIT involves the application of highly technical and complex provisions of the Code as to which there are only limited judicial and administrative interpretations and involves the determination of facts and circumstances not entirely within our control. Future legislation, new regulations, administrative interpretations or court decisions may significantly change the tax laws or the application of the tax laws with respect to qualification as a REIT for federal income tax purposes or the federal income tax consequences of such qualification.

In addition, we currently hold certain of our properties through subsidiaries that have elected to be taxed as REITs and we may in the future determine that it is in our best interests to hold one or more of our other properties through one or more subsidiaries that elect to be taxed as REITs. If any of these subsidiaries fails to qualify as a REIT for federal income tax purposes, then BXP may also fail to qualify as a REIT for federal income tax purposes.

If BXP or any of its subsidiaries that are REITs fails to qualify as a REIT then, unless certain relief provisions apply, it will face serious tax consequences that will substantially reduce the funds available for payment of dividends for each of the years involved because:

• BXP would not be allowed a deduction for dividends paid to stockholders in computing its taxable income and would be subject to federal income tax at regular corporate rates;

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• BXP also could be subject to the federal alternative minimum tax for tax years ending before January 1, 2018 and possibly increased state and local taxes; and

• unless BXP is entitled to relief under statutory provisions, BXP could not elect to be subject to tax as a REIT for four taxable years following the year during which it was disqualified.

In addition, if BXP fails to qualify as a REIT and the relief provisions do not apply, it will no longer be required to pay dividends. As a result of all these factors, BXP’s failure to qualify as a REIT could impair our ability to raise capital and expand our business, and it would adversely affect the value of BXP’s common stock. If BXP or any of its subsidiaries that are REITs fails to qualify as a REIT but is eligible for certain relief provisions, then it may retain its status as a REIT, but may be required to pay a penalty tax, which could be substantial.

In order to maintain BXP’s REIT status, we may be forced to borrow funds during unfavorable market conditions.

In order to maintain BXP’s REIT status, we may need to borrow funds on a short-term basis to meet the REIT distribution requirements, even if the then-prevailing market conditions are not favorable for these borrowings. To qualify as a REIT, BXP generally must distribute to its stockholders at least 90% of its taxable income each year, excluding capital gains and with certain other adjustments. In addition, BXP will be subject to a 4% nondeductible excise tax on the amount, if any, by which dividends paid in any calendar year are less than the sum of 85% of ordinary income, 95% of capital gain net income and 100% of undistributed income from prior years. We may need short-term debt or long-term debt or proceeds from asset sales, creation of joint ventures or sales of common stock to fund required distributions as a result of differences in timing between the actual receipt of income and the recognition of income for federal income tax purposes, or the effect of non-deductible capital expenditures, the creation of reserves or required debt or amortization payments. Any inability of our cash flows to cover our distribution requirements could have an adverse impact on our ability to raise short- and long-term debt or sell equity securities in order to fund distributions required to maintain BXP’s REIT status.

We may be subject to adverse legislative or regulatory tax changes that could negatively impact our financial condition.

At any time, the U.S. federal income tax laws governing REITs or the administrative interpretations of those laws may be amended, including with respect to our hotel ownership structure. We cannot predict if or when any new U.S. federal income tax law, regulation, or administrative interpretation, or any amendment to any existing U.S. federal income tax law, Treasury regulation or administrative interpretation, will be adopted, promulgated or become effective and any such law, regulation, or interpretation may take effect retroactively. BXP, its taxable REIT subsidiaries, and our securityholders could be adversely affected by any such change in, or any new, U.S. federal income tax law, Treasury regulation or administrative interpretation.

We face possible adverse state and local tax audits and changes in state and local tax laws.

Because BXP is organized and qualifies as a REIT, it is generally not subject to federal income taxes, but we are subject to certain state and local taxes. In the normal course of business, certain entities through which we own real estate either have undergone, or are currently undergoing, tax audits. Although we believe that we have substantial arguments in favor of our positions in the ongoing audits, in some instances there is no controlling precedent or interpretive guidance on the specific point at issue. Collectively, tax deficiency notices received to date from the jurisdictions conducting the ongoing audits have not been material. However, there can be no assurance that future audits will not occur with increased frequency or that the ultimate result of such audits will not have a material adverse effect on our results of operations.

From time to time changes in state and local tax laws or regulations are enacted, which may result in an increase in our tax liability. A shortfall in tax revenues for states and municipalities in which we operate may lead to an increase in the frequency and size of such changes. If such changes occur, we may be required to pay additional taxes on our assets or income. These increased tax costs could adversely affect our financial condition and results of operations and the amount of cash available for the payment of dividends and distributions to our securityholders.

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General Risk Factors

Changes in market conditions could adversely affect the market price of BXP’s common stock.

As with other publicly traded equity securities, the value of BXP’s common stock depends on various market conditions that may change from time to time. Among the market conditions that may affect the value of BXP’s common stock are the following:

• the extent of investor interest in our securities;

• the general reputation of REITs and the sentiment towards the office sector and the attractiveness of our equity securities in comparison to other equity securities, including securities issued by other real estate-based companies;

• our underlying asset value;

• investor confidence in the stock and bond markets, generally;

• national economic conditions;

• changes in tax laws;

• our financial performance;

• changes in our credit ratings;

• differences between the yields paid on other investments available in the market and BXP’s dividend yield; and

• general stock and bond market conditions, including changes in interest rates.

The market value of BXP’s common stock is based primarily upon the market’s perception of our growth potential and our current and potential future earnings and cash dividends. Consequently, BXP’s common stock may trade at prices that are greater or less than BXP’s net asset value per share of common stock. If our future earnings or cash dividends are less than expected, it is likely that the market price of BXP’s common stock will diminish.

Further issuances of equity securities may be dilutive to current securityholders.

The interests of our existing securityholders could be diluted if additional equity securities are issued to finance future developments, acquisitions or repay indebtedness. Our ability to execute our business strategy depends on our access to an appropriate blend of debt financing, including unsecured lines of credit and other forms of secured and unsecured debt, and equity financing, including common and preferred equity.

The number of shares available for future sale could adversely affect the market price of BXP’s stock.

In connection with and subsequent to BXP’s initial public offering, we have completed private placement transactions in which shares of stock of BXP or partnership interests in BPLP were issued to owners of properties we acquired or to institutional investors. This common stock, or common stock issuable in exchange for such partnership interests in BPLP, may be sold in the public securities markets over time under registration rights we granted to these investors. Additional common stock issuable under our employee benefit and other incentive plans, including as a result of the grant of stock options and restricted equity securities, may also be sold in the market at some time in the future. Future sales of BXP common stock in the market could adversely affect the price of its common stock. We cannot predict the effect the perception in the market that such sales may occur will have on the market price of BXP’s common stock.

Our involvement in legal proceedings and other claims may result in substantial monetary and other costs that have a material adverse effect on our results of operations.

From time to time, we are involved in legal proceedings and other claims. We may also be named as defendants in lawsuits allegedly arising out of our actions or the actions of our vendors, contractors, clients or other contractual parties in which such parties have agreed to indemnify, defend and hold us harmless from and against various claims, litigation and liabilities arising in connection with their respective businesses and/or added as an additional insured under certain insurance policies. An unfavorable resolution of any legal proceeding or other claim could have a material adverse effect on our financial condition or results from operations. Regardless of their outcome, legal proceedings and other claims may result in substantial costs and expenses and significantly divert

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the attention of our management. With respect to any legal proceeding or other claim, there can be no assurance that we will be able to prevail, or achieve a favorable settlement or outcome, or that our insurance or the insurance and/or any contractual indemnities of our vendors, contractors, clients or other contractual parties will be sufficient to cover all of our defense costs or any resulting liabilities.

Changes in accounting pronouncements could adversely affect our operating results, in addition to the reported financial performance of our clients.

Accounting policies and methods are fundamental to how we record and report our financial condition and results of operations. Uncertainties posed by various initiatives of accounting standard-setting by the Financial Accounting Standards Board and the Securities and Exchange Commission, which create and interpret applicable accounting standards for U.S. companies, may change the financial accounting and reporting standards or their interpretation and application of these standards that govern the preparation of our financial statements. Changes include, but are not limited to, changes in revenue recognition, lease accounting and the adoption of accounting standards likely to require the increased use of “fair-value” measures.

These changes could have a material impact on our reported financial condition and results of operations. In some cases, we could be required to apply a new or revised standard retroactively, resulting in potentially material restatements of prior period financial statements. Similarly, these changes could have a material impact on our clients’ reported financial condition or results of operations or could affect our clients’ preferences regarding leasing real estate.

MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE

CONTROLS AND PROCEDURES

OTHER INFORMATION

DISCLOSURE REGARDING FOREIGN JURISDICTIONS THAT PREVENT INSPECTIONS

PART III

DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE

EXECUTIVE COMPENSATION

SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS

CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE

PRINCIPAL ACCOUNTANT FEES AND SERVICES

PART IV

EXHIBITS AND FINANCIAL STATEMENT SCHEDULES

FORM 10-K SUMMARY

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Summary of Risk Factors

The risk factors detailed in Item 1A titled “Risk Factors” in this Annual Report on Form 10-K are the risks that we believe are material to our investors and a reader should carefully consider them. Those risks are not all of the risks we face and other factors not presently known to us or that we currently believe are immaterial may also affect our business if they occur. The following is a summary of the risk factors detailed in Item 1A:

• Our performance depends upon the economic conditions, particularly the supply and demand characteristics, of our markets—Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC.

• Market and economic volatility due to adverse economic and political conditions, health crises or dislocations in the credit markets could have a material adverse effect on our results of operations, financial condition and ability to pay dividends and/or distributions.

• Our success depends on key personnel whose continued service is not guaranteed.

• Our performance and value are subject to risks associated with our real estate assets and with the real estate industry, including, without limitation:

• potential difficulties or delays renewing leases or re-leasing space;

• sustained changes in client preferences and space utilization from full-time, collective in-person work environments to hybrid or remote work models and/or changes from workforce reduction due to artificial intelligence, which could decrease overall demand for workplaces and negatively impact market rental rates and property values;

• potential delays in completion of development and redevelopment projects due to supply chain disruptions and labor shortages; and

• potential increases in costs to maintain, renovate and develop our properties related to inflation.

• We face potential adverse effects from major clients’ bankruptcies or insolvencies.

• Our actual costs to develop properties may exceed our budgeted costs.

• Our use of joint ventures may limit our control over jointly owned investments and limit our flexibility to acquire other assets.

• We face risks associated with the use of debt to fund acquisitions and developments, including refinancing risk.

• Our maturing debt bears interest at lower rates than the current market rates, which has increased, and may continue to increase our interest costs which could adversely impact our ability to refinance existing debt or sell assets on favorable terms or at all.

• Covenants in our debt agreements could adversely affect our financial condition.

• Our degree of leverage could limit our ability to obtain additional financing or affect the market price of our equity and debt securities.

• We face risks associated with security breaches, incidents and compromises through cyber attacks, cyber intrusions or otherwise, as well as other significant disruptions of our information technology (IT) networks and related systems.

• The use of technology based on artificial intelligence and machine learning presents risks and challenges that may adversely affect our business and results of operations.

• We face risks associated with climate change and severe weather events, as well as the regulatory efforts intended to reduce the effects of climate change.

• Potential liability for environmental contamination could result in substantial costs.

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• Some potential losses are not covered by insurance.

• Our involvement in legal proceedings and other claims may result in substantial monetary and other costs that have a material adverse effect on our results of operations.

• We face risks associated with BXP’s status as a real estate investment trust (REIT), including, without limitation:

• failure to qualify as a REIT would cause BXP to be taxed as a corporation, which would substantially reduce funds available for payment of dividends;

• possible adverse state and local tax audits and changes in state and local tax laws could result in increased tax costs that could adversely affect our financial condition and results of operations and the amount of cash available for the payment of dividends and distributions to our securityholders; and

• in order to maintain BXP’s REIT status, we may be forced to borrow funds during unfavorable market conditions.

This section contains forward-looking statements. You should refer to the explanation of the qualifications and limitations on forward-looking statements beginning on page 52 .

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PART I.

Item 1 . Business

General

BXP, a Delaware corporation, is a fully integrated, self-administered and self-managed REIT, and it is one of the largest publicly-traded office REITs (based on total market capitalization as of December 31, 2025) in the United States that develops, owns and manages primarily premier workplaces. BXP was formed in 1997 to succeed the real estate development, redevelopment, acquisition, management, operating and leasing businesses associated with the predecessor company founded by Mortimer B. Zuckerman and Edward H. Linde in 1970.

Our properties are concentrated in six dynamic gateway markets—Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC. At December 31, 2025, we owned or had joint venture interests in a portfolio of 179 commercial real estate properties, aggregating approximately 52.6 million net rentable square feet of primarily premier workplaces, including eight properties under construction/redevelopment totaling approximately 3.5 million net rentable square feet. As of December 31, 2025, our properties consisted of:

• 157 office properties (including four properties under construction/redevelopment);

• 14 retail properties (including one property under construction);

• seven residential properties (including three properties under construction); and

• one hotel.

We consider premier workplaces to be well-located buildings that are modern structures or have been modernized to compete with newer buildings, are professionally managed and maintained, and offer a number and type of amenities that are in high demand by clients that are focused on the importance of the physical work environment in recruiting and retaining the best and brightest employees. As such, these properties attract creditworthy clients and command upper-tier rental rates in their markets. We do not consider the expression “premier workplaces” a classification of our properties in accordance with any standard listing criteria in the real estate industry. We therefore caution investors that our use and definition of “premier workplaces” may be different than the use and definition of similar expressions and traditional classifications that may be used by other companies.

We are a full-service real estate company, with substantial in-house expertise and resources in acquisitions, development, financing, capital markets, construction management, property management, marketing, leasing, accounting, risk management, tax and legal services. For this reason, we refer to our tenants as “clients” due to the many facets of our continuous engagements with them, which span beyond the usual tenant/landlord relationship. Throughout this Annual Report, we use the terms “tenant” and “client” interchangeably.

BXP manages BPLP as its sole general partner. Our principal executive office and Boston regional office are located at The Prudential Center, 800 Boylston Street, Suite 1900, Boston, Massachusetts 02199 and our telephone number is (617) 236-3300. In addition, we have regional offices at 2800 28th Street, Santa Monica, California 90405, 599 Lexington Avenue, New York, New York 10022, Two Embarcadero Center, San Francisco, California 94111, 1001 Fourth Avenue, Seattle, Washington 98154 and 2200 Pennsylvania Avenue NW, Washington, DC 20037.

Our internet address is http://www.bxp.com. On our website, you can obtain free copies of our Annual Reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, including exhibits, and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended, as soon as reasonably practicable after we electronically file such material with, or furnish it to, the Securities and Exchange Commission, or the SEC. You may also obtain BXP’s and BPLP’s reports by accessing the EDGAR database at the SEC’s website at http://www.sec.gov, or we will furnish an electronic or paper copy of these reports free of charge upon written request to: Investor Relations, BXP, Inc., Prudential Center, 800 Boylston Street, Suite 1900, Boston, Massachusetts 02199. “Boston Properties” is a registered trademark, BXP is a registered trademark, and the “bxp” logo is a registered trademark, in all cases, owned by BPLP.

Boston Properties Limited Partnership

BPLP is a Delaware limited partnership organized in 1997, and the entity through which BXP conducts substantially all of its business and owns, either directly or through subsidiaries, substantially all of its assets. BXP is the sole general partner of BPLP and, as of February 20, 2026, the owner of approximately 89.4% of the economic interests in BPLP. Economic interest was calculated as the number of common partnership units of BPLP

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owned by BXP as a percentage of the sum of (1) the actual aggregate number of outstanding common partnership units of BPLP and (2) the number of common units issuable upon conversion of all outstanding long term incentive plan units of BPLP (“LTIP Units”), for which all performance conditions have been satisfied for such conversion. We exclude from (1) and (2) above other LTIP Units issued in the form of Multi-Year Long-Term Incentive Plan Awards in 2024 or later (“MYLTIP Awards or MYLTIP Units”) and 2025 Outperformance Plan Awards (“2025 OPP Awards or 2025 OPP Units”), which remain subject to performance conditions. An LTIP Unit is generally the economic equivalent of a share of BXP’s restricted common stock, although LTIP Units issued in the form of MYLTIP Awards and 2025 OPP Awards are only entitled to receive one-tenth (1/10th) of the regular quarterly distributions (and no special distributions) prior to being earned.

Transactions During 2025

Acquisitions

During the year ended December 31, 2025, we acquired 2100 M Street, a vacant office building, located in Washington, DC, for a purchase price, including transaction costs, of approximately $55.9 million of cash. We intend to redevelop this site in the future (See Note 3 to the Consolidated Financial Statements).

Dispositions and Impairments

During the year ended December 31, 2025, excluding our unconsolidated joint ventures, we completed eight sales transactions for an ag gregate gross sales price of approximately $702.6 million, resulting in net proceeds of approximately $682.5 million and gains on sales of real estate of $175.0 million and $177.6 million for BXP and BPLP, respectively (See Note 3 to the Consolidated Financial Statements). .

During the year ended December 31, 2025 , we evaluated the consolidated properties approved by BXP’s Board of Directors (or a committee thereof) for sale to third-parties, which resulted in recognized impairment losses of approximately $85.8 million and $82.9 million for BXP and BPLP, respectively (See Notes 2 and 3 to the Consolidated Financial Statements).

Developments /Redevelopments

During the year ended December 31, 2025, we commenced development/redevelopment of four properties, including 343 Madison Avenue in New York City, New York, aggregating approximately 1.9 million in estimated net rentable square feet when complete. Our share of the aggregated estimated total investment to complete these properties is approximately $2.1 billion. We also partially or fully placed in-service four properties that totaled approximately 727,000 net rentable square feet (See Notes 3 and 6 to the Consolidated Financial Statements).

As of December 31, 2025, we had eight properties under construction/redevelopment, aggregating approximately 3.5 million in estimated net rentable square feet when completed. We estimate our share of the aggregate estimated total investment to complete these projects is approximately $3.9 billion, of which approximately $2.5 billion remained to be invested as of December 31, 2025. The total development pipeline, including office, laboratory/life sciences and retail developments, but excluding our residential developments, is 61% pre-leased as of February 20, 2026. For a detailed list of the properties under construction/redevelopment see “Liquidity and Capital Resources” within “Item 7—Management’s Discussion and Analysis of Financial Condition and Results of Operations.”

Debt

During the year ended December 31, 2025, BXP further strengthened its balance sheet by addressing debt maturities and sourcing additional liquidity in the capital markets. In the aggregate, excluding our unconsolidated joint ventures, our debt market activities totaled approximately $4.2 billion, underscoring BXP’s consistent access to debt capital. For additional details on each of the transactions listed below, refer to Note 7 to the Consolidated Financial Statements.

Notable transactions during 2025 include:

• Repaid $850.0 million of 3.20% unsecured senior notes due January 15, 2025,

• Upsized the unsecured commercial paper program from $500.0 million to $750.0 million in March 2025,

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• Extended the maturity date for the $700.0 million unsecured term loan to 2030 (inclusive of extension options) in March 2025,

• Upsized the amended and restated revolving credit agreement from $2.0 billion to $2.25 billion and extended its maturity date to 2030 in March 2025, and

• Issued $1.0 billion of 2.00% unsecured exchangeable senior notes due 2030 in September 2025.

Hedging Transaction

On April 8, 2025, BPLP entered into an interest rate swap contract with a notional amount of $300.0 million to replace $300.0 million of interest rate swap contracts that expired on April 1, 2025. The interest rate swap was entered into to fix Daily Simple SOFR, at a fixed interest rate of 3.6775% per annum for the period commencing on April 7, 2025, the effective date, and ending on April 6, 2026 (See Note 8 to the Consolidated Financial Statements).

Equity Transactions

During the year ended December 31, 2025, BXP acquired an aggregate of 291,040 common units of limited partnership interest, including a total of 87,398 common units issued upon the conversion of LTIP Units, 2012 outperformance plan awards (“2012 OPP Units”) and 2013 - 2021 multi-year, long-term incentive program awards, presented by the holders for redemption, in exchange for an equal number of shares of BXP common stock.

Investments in Unconsolidated Joint Ventures

For additional details on each of the transactions listed below, refer to Note 6 to the Consolidated Financial Statements.

During the year ended December 31, 2025, our unconsolidated joint ventures further strengthened their balance sheets by addressing debt maturities and sourcing additional liquidity in the capital markets. In the aggregate, their debt market activities totaled approximately $1.2 billion of which our share was approximately $0.5 billion. Notable transactions during 2025 include:

• Executed a new $252.0 million non-recourse CMBS financing secured by our 7750 Wisconsin Avenue joint venture in Bethesda, Maryland in February 2025. This new loan was used to repay the existing $252.0 million construction loan. We have a 50% ownership interest in the joint venture.

• Executed a new $225.0 million construction loan secured by our 290 Coles Street joint venture in Jersey City, New Jersey in March 2025. We have a 19.46% ownership interest in the joint venture.

• Executed a new $98.7 million construction loan secured by our 17 Hartwell Street joint venture in Lexington, Massachusetts in June 2025. We have a 20% ownership interest in the joint venture.

• Executed a new $465.0 million non-recourse CMBS financing secured by our Hub on Causeway - Podium and 100 Causeway Street joint ventures in Boston, Massachusetts in October 2025. This new loan was used to repay the existing loans aggregating approximately $490.0 million. We have a 50% ownership interest in the joint ventures.

• Executed a (1) new $108.0 million senior loan and (2) $50.0 million mezzanine loan secured by our 3 Hudson Boulevard joint venture in New York City, New York in October 2025. These new loans were used to repay the existing $80.0 million loan that was provided by us to the joint venture. We have a 25% ownership interest in the joint venture and are the lender for the mezzanine loan.

• Repaid the approximately $198.4 million construction loan secured by our Dock 72 joint venture in Brooklyn, New York in October 2025. We have a 50% ownership interest in the joint venture.

During the year ended December 31, 2025, we completed three sale transactions related to our investments in unconsolidated joint ventures. Our share of the ag gregate gross sales price was approximately $237.7 million, resulting in our share of net proceeds of approximately $170.2 million. We recognized gains on sales related to these transactions of approximately $53.7 million, which has been included within Loss from Unconsolidated Joint Ventures on the Consolidated Financial Statements.

During the year ended December 31, 2025, we evaluated key impairment indicators related to certain investments in unconsolidated joint ventures (See Note 2 to the Consolidated Financial Statements). This

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evaluation, including a pending offer from a third-party, resulted in our determination that the decline in value for the joint venture that owns Gateway Commons was other-than-temporary. As a result, we recognized an other-than-temporary impairment loss on our investment in Gateway Commons of approximately $145.1 million.

Noncontrolling Interest

On August 27, 2025, we acquired our partner’s 45% ownership interest in the consolidated entity that is developing the 343 Madison Avenue project located in New York City, New York for approximately $43.5 million of cash. The acquisition price equaled the partner’s aggregate unreturned capital contributions to the joint venture. Prior to the acquisition, we had a 55% ownership interest in the joint venture.

Stock Option and Incentive Plan

For additional details on each of the transactions listed below, refer to Note 15 to the Consolidated Financial Statements.

On January 22, 2025, BXP’s Compensation Committee approved the 2025 Multi-Year Long-Term Incentive Program (the “2025 MYLTIP”) awards under the BXP, Inc. 2021 Stock Incentive Plan (the “2021 Plan”) to certain executive officers of BXP. Under Accounting Standards Codification (“ASC”) 718 “Compensation – Stock Compensation,” (“ASC 718”) the 2025 MYLTIP awards have an aggregate value of approximately $12.7 million, which amount will generally be amortized into earnings under the graded vesting method.

On January 31, 2025, the three-year measurement period for our 2022 MYLTIP awards ended and, based on BXP’s absolute and relative total shareholder return (“TSR”) performance, the final payout was determined to be 59% of target, or an aggregate of approximately $5.4 million (after giving effect to employee separations). As a result, an aggregate of 177,919 2022 MYLTIP Units that had been previously granted were automatically forfeited.

On December 22, 2025, BXP’s Compensation Committee approved the 2025 OPP Awards. Under the 2025 OPP Awards, performance and service-based equity awards were granted to certain members of BXP’s senior leadership team. The awards were issued pursuant to the 2021 Plan in the form of LTIP Units and consist of an opportunity to earn up to an aggregate of 711,864 LTIP Units. The number of LTIP Units reflects the maximum that may be earned for achieving the highest level of performance and satisfying the service-based vesting requirements. Under ASC 718 the 2025 OPP Awards have an aggregate value of approximately $31.9 million, which amount will generally be amortized into earnings under the graded vesting attribution method.

Business and Growth Strategies

Business Strategies

Our primary business objective is to maximize return on investment to provide our investors with the greatest possible total return at all points of the economic cycle. Our long-term strategies to achieve this objective are:

• to target a few carefully selected dynamic gateway markets—Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC—and to be one of the leading, if not the leading, developers, owners and managers in each of those markets with a full-service office in each market providing property management, leasing, development, construction and legal expertise. We select markets and submarkets with a diverse economic base and a deep pool of prospective clients in various industries and where clients have demonstrated a preference for premier workplaces and other facilities. Additionally, our markets have historically been able to recruit new talent to them and help sustain job growth that results in growth in rental rates and occupancy over time;

• to emphasize markets and submarkets within those markets where the difficulty of receiving the necessary approvals for development and the necessary financing constitute high barriers to the creation of new supply, and where skill, financial strength and diligence are required to successfully develop, finance and manage high-quality office as well as selected life sciences, retail and residential space;

• to take on complex, technically challenging development projects, leveraging the skills of our management team to successfully develop, acquire or reposition properties that other organizations may not have the capacity or resources to pursue;

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• to own and develop high-quality real estate designed to meet the demands of today’s clients who require sophisticated telecommunications and related infrastructure, support services, sustainable features and amenities, including those amenities that enrich in-person experiences and support a hybrid work environment, and to manage those facilities so as to become the landlord of choice for both existing and prospective clients;

• to opportunistically acquire assets that increase our market share in the markets in which we have chosen to concentrate, as well as potential new markets, which exhibit an opportunity to improve returns through repositioning (through a combination of capital improvements and shift in marketing strategy), changes in management focus and leasing;

• to explore joint venture or lending opportunities with existing property owners located in desirable locations, who seek to benefit from the depth of development and management expertise we are able to provide and our access to capital;

• to pursue on a selective basis the sale of properties or interests therein, including core properties, to either (1) take advantage of the demand for our premier properties and realize the value we have created or (2) pare from our portfolio properties that we believe have slower future growth potential;

• to seek third-party development contracts to enable us to retain and utilize our existing development and construction management staff, especially when our internal development is less active or when new development is less-warranted due to market conditions; and

• to enhance our capital structure through our access to a variety of sources of equity and debt capital and proactively manage our debt expirations.

From time to time, in response to one or more macroeconomic or other external factors, we refine our plans for achieving one or more elements of our overall strategy. At our September 2025 Investor Day, we detailed a three-year action plan focused on near-term earnings growth by leveraging BXP's operational expertise and portfolio of premier workplaces within our core gateway markets to:

• grow occupancy;

• develop premier assets with a focus on projects underway and a selective approach to future opportunities;

• execute on a multi-year asset sales program to dispose of non-income producing land, select residential, and non-strategic and select strategic office assets, with proceeds designated to reduce leverage and fund our development pipeline; and

• secure private equity partnerships on select assets to complement other funding sources and increase investment yields.

We believe the components of this strategic action plan align with our broader, long-term strategy of maintaining leadership in core markets, prudently growing the portfolio, and disciplined capital allocation to drive shareholder value. We may achieve the goals underlying this strategic action plan through a variety of methods and the timing, extent and impact of any transactions that we have or will undertake while implementing this strategic action plan may vary and evolve.

Growth Strategies

External Growth Strategies

We believe that our development experience, our organizational depth, utilization of our joint venture partner relationships and our balance sheet position us to continue to selectively develop a range of premier workplaces, including high-rise urban developments, mixed-use developments (including office, residential and retail), low-rise suburban office and residential properties, within budget and on schedule. We believe we are also well-positioned to achieve external growth through acquisitions. From time to time, we remove from service select office assets for which we believe we have better uses, such as residential developments. Other factors that contribute to our competitive position include:

• our control of sites in our markets that could support, as of December 31, 2025, approximately 13.6 million and 4.7 million of additional square feet of new office and residential developments, respectively;

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• our reputation gained through 56 years of successful operations and the stability and strength of our existing portfolio of properties;

• our relationships with leading national corporations, universities and public institutions, including government agencies, seeking new facilities and development services;

• our relationships with nationally recognized financial institutions that provide capital to the real estate industry;

• our track record and reputation for executing acquisitions efficiently provide comfort to domestic and foreign institutions, private investors and business entities who seek to sell commercial real estate in our market areas;

• our ability to act quickly on due diligence and financing;

• our relationships with institutional buyers and sellers of high-quality real estate assets;

• our ability to procure entitlements from multiple municipalities to develop and/or sell sites and attract land owners to sell to or partner with us; and

• our relationship with domestic and foreign investors who seek to partner with companies like ours.

Opportunities to execute our external growth strategy fall into three categories:

• Development in selected submarkets. We believe the selective development of well-positioned premier workplaces, as well as residential buildings and mixed-use complexes, may be justified in certain of our markets. We believe in acquiring land after taking into consideration timing factors relating to economic cycles and in response to market conditions that should allow for its development at the appropriate time. While we purposely concentrate in markets with high barriers-to-entry, we have demonstrated throughout our 56-year history an ability to make carefully timed land acquisitions in submarkets where we can become one of the market leaders in establishing rent and other business terms. We believe that there are opportunities at key locations in our existing and other markets for a well-capitalized developer to acquire land or buildings with development or redevelopment potential.

We seek complex projects where we can add value through the efforts of our experienced and skilled management team leading to attractive returns on investment. In the past, we have been particularly successful at acquiring sites or options to purchase sites that need governmental approvals for development. Because of our development expertise, knowledge of the governmental approval process and reputation for quality development with local government regulatory bodies, we generally have been able to secure the permits necessary to allow development and to profit from the resulting increase in land value.

Our strong regional relationships and recognized development expertise have also enabled us to capitalize on unique build-to-suit opportunities. We intend to seek and expect to continue to be presented with such opportunities in the near term allowing us to earn relatively significant returns on these development opportunities through multiple business cycles.

• Acquisition of assets and portfolios of assets from institutions, including lenders, or individuals. We believe that due to our size, management strength and reputation, we are well positioned to acquire portfolios of assets or individual properties from institutions or individuals if valuations meet our criteria. In addition, we believe that our market knowledge, our liquidity and access to capital may provide us with a competitive advantage when pursuing acquisitions. Opportunities to acquire properties may also come through the purchase of first mortgage or mezzanine debt. We are also able to appeal to sellers wishing to contribute on a tax-deferred basis their ownership of property for equity in a diversified real estate operating company that offers liquidity through access to the public equity markets in addition to a quarterly distribution. Our ability to offer common and preferred units of limited partnership in BPLP to sellers who would otherwise recognize a taxable gain upon a sale of assets for cash or BXP’s common stock may facilitate these types of acquisitions on a tax-efficient basis. Existing promulgated Treasury regulations may limit the tax benefits previously available to sellers in some variations of these transactions.

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• Acquisition of underperforming assets and portfolios of assets . We believe that because of our in-depth market knowledge and development experience in each of our markets, our national reputation with brokers, financial institutions, owners of real estate and others involved in the real estate market and our access to competitively-priced capital, we are well-positioned to identify and acquire existing, underperforming properties for competitive prices and to add significant additional value to such properties through our effective marketing strategies, repositioning/redevelopment expertise and a responsive property management program.

Internal Growth Strategies

We believe that opportunities will exist to increase cash flow from our existing properties through an increase in occupancy and rental rates because they are of high quality and in desirable locations. Additionally, our markets have diversified economies that have historically experienced job growth and increased use of office space, resulting in growth in rental rates and occupancy over time. Our strategy for maximizing the benefits from these opportunities is three-fold: (1) to provide high-quality property management services using our employees in order to encourage clients to renew, expand and relocate in our properties, (2) to achieve speed and transaction cost efficiency in replacing departing clients through the use of in-house services for marketing, lease negotiation and construction of tenant and capital improvements and (3) to work with new or existing clients with space expansion or contraction needs, leveraging our expertise and clustering of assets to maximize the cash flow from our assets. We expect to continue our internal growth as a result of our ability to:

• Carefully select submarkets and cultivate long-term relationships with creditworthy clients. In choosing locations for our properties, we have paid particular attention to transportation and commuting patterns, physical environment, adjacency to established business centers and amenities, proximity to sources of business growth and other local factors that we believe our clients demand.

At December 31, 2025, the weighted-average lease term of our in-place leases based on square feet, including leases signed by our unconsolidated joint ventures, was approximately 7.9 years and we continue to cultivate long-term leasing relationships with a diverse base of high-quality, financially stable clients. In 2025, we executed approximately 5.6 million square feet of leases with a weighted-average lease term of 10.1 years. Based on leases in place at December 31, 2025, leases with respect to approximately 2.6%, or approximately 1.2 million square feet, of the total square feet in our portfolio, including unconsolidated joint ventures but excluding Gateway Commons and North First Business Park, will expire in calendar year 2026.

• Directly manage our office properties to maximize the potential for client retention. We provide property management services ourselves, rather than contracting for this service, to maintain awareness of and responsiveness to client needs. We and our properties also benefit from cost efficiencies produced by an experienced work force attentive to preventive maintenance and energy management and from our continuing programs to assure that our property management personnel at all levels remain aware of their important role in client relations. In addition, we reinvest in our properties by adding new services and amenities that are desirable to our clients.

• Replace clients quickly at best available market terms and lowest possible transaction costs . We believe that we are well-positioned to attract new clients and achieve relatively high rental and occupancy rates as a result of our well-located, well-designed and well-maintained properties, our reputation for high-quality building services and responsiveness to clients, and our ability to offer expansion and relocation alternatives within our submarkets.

• Extend terms of existing leases to existing clients prior to expiration . We have also successfully structured early client renewals, which have reduced the cost associated with lease downtime while securing the tenancy of our highest quality credit-worthy clients on a long-term basis and enhancing relationships.

• Re-development of existing assets. We believe the select re-development of assets within our portfolio, where through the ability to increase the building size and/or to increase cash flow and generate appropriate returns on incremental investment after consideration of the asset’s current and future cash flows, may be desirable. This generally occurs in situations in which we are able to increase the building’s size, improve building systems, including conversion to higher yielding uses, and sustainability features, and/or add client amenities, thereby increasing client demand, generating acceptable returns

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on incremental investment and enhancing the long-term value of the property and the company. In the past, we have been particularly successful at gaining local government approval for increased density at several of our assets, providing the opportunity to enhance value at a particular location. Our strong regional relationships and recognized re-development expertise have enabled us to capitalize on unique build-to-suit opportunities. We intend to seek and expect to continue to be presented with such opportunities in the near term allowing us to earn attractive returns on these development opportunities through multiple business cycles.

Sustainability

Our Strategy

We are committed to maximizing long-term value for our shareholders through, among other strategies, actively working to promote our growth and operations sustainably and responsibly across our six dynamic gateway markets. BXP’s sustainability strategy is to conduct our business, the development, ownership and operation of new and existing buildings, in a manner that contributes to positive outcomes for our clients, shareholders, employees and the communities in which we operate (collectively, our “stakeholders”). We are focused on developing and maintaining healthy, high-performance buildings, while simultaneously mitigating operational costs and the potential external impacts of energy, water, waste, and climate change. We undertake electric, steam, and natural gas efficiency projects and procurement initiatives to reduce energy-related operating expense growth and primary fossil fuel consumption. These initiatives have also contributed to lower greenhouse gas (“GHG”) emissions and compliance with building performance standards in the New York and Boston markets. Through our efforts, we demonstrate that operating and developing commercial real estate can be conducted with a conscious regard for the environment while mutually benefiting our stakeholders.

Sustainability Leadership

BXP is a widely recognized industry leader in sustainability, and our 2025 highlights include:

• BXP achieved carbon-neutral operations for GHG emissions Scopes 1 and 2

• BXP ranked among the top real estate companies in the GRESB assessment, earning a tenth consecutive 5-star rating. 2025 was the 14th consecutive year that BXP earned the GRESB “Green Star” designation

• BXP maintained an MSCI rating of “AA” and a CDP score of “B”

• BXP was named to Newsweek’s America’s Most Responsible Companies 2026 for the sixth consecutive year, ranking in the top half of 600 companies, and was also named to Newsweek’s America’s Greenest Companies 2026 with a 5-star rating

• BXP was named a Fitwel Best in Building Health Award winner by the Center for Active Design for the ninth time

• BXP earned the City of Boston’s Building Emissions Reduction and Disclosure Ordinance's (BERDO) Energy Efficiency Spotlight, highlighting our retro-commissioning efforts in Boston

• BXP was named a Sustainalytics Low Carbon Leader

• BXP continued its tenure as an inaugural Platinum Level Green Lease Leader by the Institute for Market Transformation and the U.S. Department of Energy

Our leadership position is due, in part, to our establishment of environmental goals, the periodic reporting of progress toward our goals and the achievement of these goals, which we report in an annual Sustainability & Impact Report that is made available on our website at http://www.bxp.com under the heading “Commitment”. We have publicly adopted energy, water, building certification, waste and GHG emissions goals, including a commitment to achieving carbon-neutral operations (for direct and indirect Scope 1 and Scope 2 GHG emissions) by the end of 2025 from our occupied and actively managed buildings where we have operational control. We have also provided climate-related disclosures aligned with the recommendations of the Task Force on Climate-Related Financial Disclosures (“TCFD”). Detailed information on these goals and targets and our TCFD disclosures are included in our Sustainability & Impact Reports. We expect to publish our next report in April 2026.

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The Sustainability & Impact Reports and the related information contained on our website (or that can be accessed through our website) are not incorporated by reference into this Annual Report on Form 10-K.

Sustainability Accounting Standards Board (“SASB”) Disclosures

The Real Estate Sustainability Accounting Standard issued by SASB in 2018 proposed sustainability accounting metrics designed for disclosure in mandatory filings, such as the Annual Report on Form 10-K, and serves as the framework against which we have aligned our disclosures for sustainability information. The recommended energy and water management activity metrics for the real estate industry include energy consumption data coverage as a percentage of floor area (“Energy Intensity”); percentage of the eligible portfolio that is certified ENERGY STAR® (“ENERGY STAR certified”); total energy consumed by portfolio area (“Total Energy Consumption”); water withdrawal as a percentage of total floor area (“Water Intensity”); and total water withdrawn by portfolio area (“Total Water Consumption”). Our energy and water data is collected from utility bills and submeters and is assured by an independent, third-party assurance expert, which includes all 2024 SASB energy and water metrics. During the 2025 calendar year, 64 buildings representing 50% of BXP’s total in-service portfolio were ENERGY STAR certified. A licensed professional has verified all ENERGY STAR applications.

The charts below detail our Energy Intensity, Total Energy Consumption, Water Intensity and Total Water Consumption for 2015 through 2024 for which data were available on occupied and actively managed office buildings where we had operational control. 1,2,3,4,5,6

(1) Full 2025 calendar year energy and water data will not be available and assured by a third party until April 2026. Therefore, 2024 is the most recent year for which complete and third-party assured energy and water data is available.

(2) The charts reflect the performance of our occupied and actively managed office portfolio. We define “occupied buildings” as those with no more than 50% vacancy. Actively managed office buildings are multi-tenant buildings over which we have operational control of building system performance and investment decisions. At the end of the 2024 calendar year, our occupied and actively managed office portfolio included 75 buildings totaling 39.6 million gross square feet, and it accounted for approximately 73% of BXP’s total in-service portfolio by area.

(3) Floor area is considered to have complete energy consumption data coverage when we obtain energy consumption data (i.e., energy types and amounts consumed) for all types of energy consumed in the relevant floor area during the calendar year, regardless of when such data was obtained.

(4) The scope of energy includes energy purchased from sources external to us and our clients or produced by us or our clients and energy from all sources, including fuel, gas, electricity and steam. Energy use intensity (kBtu/SF) has been weather-normalized.

(5) Water sources include surface water (including water from wetlands, rivers, lakes and oceans), groundwater, rainwater collected directly and stored by BXP, municipal water supplies or supply from other water utilities.

(6) 2020 and 2021 data reflect the combined impacts of efficiency measures and reduced physical occupancy due to the COVID-19 pandemic.

Human Capital Management

As of December 31, 2025, we had 714 non-union employees and 112 union employees. Because the unions control the primary aspects of the hiring process, except as otherwise noted, all data provided in this Human Capital Management section refers to BXP’s non-union employee workforce only.

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Our operational and financial performance depends on the talents, energy, experience and well-being of our employees. Our ability to attract and retain talented people depends on a number of factors, including work environment, career development and professional training, compensation and benefits, and the health, safety and wellness of our employees.

Our workforce provides a strategic business advantage as it is one of our most valuable assets. We are committed to the quality, growth and development of our people as part of our strategy to drive long-term value for our shareholders. We aim to ensure that all employees have the opportunity to make their maximum contribution to us and to their own career goals. It has been, and will continue to be, our policy to recruit, hire, assign, promote and train in all job titles without regard to race, national origin, religion, age, color, sex, sexual orientation, gender identity, disability, protected veteran status, or any other characteristic protected by local, state, or federal laws, rules, or regulations. Our hiring practices do not, and have not, included quotas or numerical targets based on any of these characteristics.

Culture & Employee Engagement

We believe that the success of our business is tied to the quality of our workforce, and we strive to maintain a corporate environment without losing the entrepreneurial spirit with which we were founded more than 55 years ago. By providing a quality workplace and comprehensive benefit programs, we recognize the commitment of our employees to bring their talent, energy and experience to us. Our continued success will depend on our employees’ expertise and dedication. Our workforce, as referred to in this section, excludes intern employees and union employees for which the unions control primary aspects of the hiring process.

We periodically conduct employee engagement surveys to monitor our employees’ satisfaction in different aspects of their employment, including company performance, leadership, communication, career development and benefits offerings. Past employee responsiveness to the engagement surveys has been consistently high and the results help inform us on matters that our employees view as key contributors to a positive work experience. Based on the most recent employee engagement survey conducted in 2025, with a 93% response rate, the overall company-wide result was a “favorable” rating. The results affirmed that BXP is healthy across core areas such as company performance, leadership and management. We intend to continue to periodically evaluate employee engagement as needed on a meaningful basis.

Another indicator of the success of our efforts in the workplace is the long tenure of our employees. Approximately 34% of our employees have worked at BXP for ten or more years. The average tenure of our employees is approximately 9.8 years and that of our officers is 18.3 years. In 2025, our voluntary workforce turnover rate was 7.6%.

Career Development & Training

We invest significant resources in our employees’ personal and professional growth and development and provide a wide range of tools and development opportunities that build and strengthen employees’ leadership and professional skills. These development opportunities include in-person and virtual training sessions, in-house learning opportunities, various management trainings, departmental conferences, executive town halls and external programs. We foster an environment of growth and internal promotion and strive for a process that is grounded in efficiency, transparency and collaboration for our internal candidates. Open positions are posted, and employees are highly encouraged to apply for promotion within the organization. In 2025, more than 7% of our employees were promoted to elevated roles within our organization.

Compensation & Benefits

We designed our compensation program with the goal of providing a balanced and effective way of ensuring internal equity and market competitiveness in our pay practices. We have coupled external market-driven data with a comprehensive performance review assessment tool to strike the balance that best represents our compensation strategy and links pay to performance. On an annual basis, our Human Resources department evaluates market compensation ranges for each position to ensure we are appropriately compensating our employees. We believe this total rewards program directly aligns with our compensation and benefits strategy.

Our employee benefit programs are thoughtfully designed to meet the needs of our workforce by offering comprehensive and competitive programs to support our employees and their families. These programs provide flexibility and choice in coverage, valuable resources to protect and enhance financial security, and benefits that help balance work and personal life. Some of the benefits that we offer our employees include:

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• health (including telehealth), dental and vision insurance,

• employer-subsidized health savings account,

• a 401(k) plan with a generous company matching contribution,

• an employee stock purchase plan that allows employees to purchase our common stock at a discount,

• health care and dependent care flexible spending accounts,

• income protection through our sick pay, salary continuation, long-term disability policies and life insurance and AD&D insurance,

• business travel accident insurance,

• a scholarship program for the children of non-officer employees,

• tuition reimbursement,

• a commuter subsidy to encourage and support the use of public transportation,

• paid vacation, holiday, personal days, a volunteer day program, and paid parental leave to balance work and personal life,

• wellness and mental health well-being programs,

• employee assistance program,

• matching charitable gift program,

• back-up care for children and elders, and

• pet insurance.

Health, Safety & Wellness

As one of the largest publicly traded premier workplace REITs (based on total market capitalization as of December 31, 2025) in the United States, we appreciate the influence of buildings on human health and its importance to our clients and employees. The health, safety and security of our employees, clients, contractors and other visitors to our properties are our highest priority. We have implemented numerous operational measures to promote better health and safety in our buildings, including measures related to indoor air quality in our buildings.

We believe the success of our employees is dependent upon their overall well-being, including their physical health, mental health, work-life balance and financial well-being. In addition to the benefits outlined above, we also offer our employees an Employee Wellness Program, an Employee Assistance Program and a Mental Health Well-Being Program. The Employee Wellness Program was established in 2016 to encourage employees to improve their health and well-being by offering a variety of activities and engaging content to meet individual wellness goals. Qualifying program participants receive a discount on a portion of their health insurance cost. The Employee Assistance Program includes services for childcare, eldercare, personal or work-related relationships, financial planning assistance, stress management, mental health, general wellness and self-help. BXP also offers a premium mental health wellbeing program that provides online resources and support for employees facing a wide variety of issues.

Policies with Respect to Certain Activities

The discussion below sets forth certain additional information regarding our investment, financing and other policies. These policies have been determined by BXP’s Board of Directors and, in general, may be amended or revised from time to time by the Board of Directors.

Investment Policies

Investments in Real Estate or Interests in Real Estate

Our investment objectives are to provide quarterly cash dividends/distributions to our securityholders and to achieve long-term capital appreciation through increases in our value. We have not established a specific policy regarding the relative priority of these investment objectives.

We expect to continue to pursue our investment objectives primarily through the ownership of our current properties, development and redevelopment projects and other acquired properties. We currently intend to continue to invest primarily in developments of properties and acquisitions of existing improved properties or properties in

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need of redevelopment, and acquisitions of land that we believe have development potential, primarily in our existing markets of Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC. We have explored and may continue to explore for future investment in select domestic and international markets that exhibit these same traits. Future investment or development activities will not be limited to a specified percentage of our assets. We intend to engage in such future investment or development activities in a manner that is consistent with the maintenance of BXP’s status as a REIT for federal income tax purposes. In addition, we may purchase or lease income-producing commercial and other types of properties for long-term investment, expand and improve the real estate presently owned or other properties purchased, or sell such real estate properties, in whole or in part, when circumstances warrant. We do not have a policy that restricts the amount or percentage of assets that will be invested in any specific property, however, our investments may be restricted by our debt covenants.

We may also continue to participate with third parties in property ownership, through joint ventures or other types of co-ownership. These investments may permit us to own interests in larger assets without unduly restricting diversification and, therefore, add flexibility in structuring our portfolio.

Equity investments may be subject to existing mortgage financing and other indebtedness or such financing or indebtedness as may be incurred in connection with acquiring or refinancing these investments. Debt service on such financing or indebtedness will have a priority over any distributions with respect to BXP’s common stock. Investments are also subject to our policy not to be treated as an investment company under the Investment Company Act of 1940, as amended (the “1940 Act”).

Investments in Real Estate Mortgages and Mezzanine Debt

While our current portfolio consists primarily of, and our business objectives emphasize, equity investments in commercial real estate, we may, at the discretion of the Board of Directors of BXP, invest in mortgages and other types of real estate interests consistent with BXP’s qualification as a REIT. Investments in real estate mortgages run the risk that one or more borrowers may default under the mortgages and that the collateral securing such mortgages may not be sufficient to enable us to recoup our full investment. We may invest in participating, convertible or traditional mortgages if we conclude that we may benefit from the cash flow, or any appreciation in value of the property or as an entrance to the fee ownership. As of December 31, 2025, we had one note receivable and two related-party note receivables outstanding, which totaled approximately $37.7 million, after adjustments for financing costs and the current expected credit loss allowance.

Securities of or Interests in Entities Primarily Engaged in Real Estate Activities

Subject to the percentage of ownership limitations and gross income and asset tests necessary for BXP’s REIT qualification and our debt covenants, we also may invest in securities of other REITs, other entities engaged in real estate activities or securities of other issuers, including for the purpose of exercising control over such entities.

Dispositions

Our long-term business strategy includes selective asset sales from time to time. In general, we decide to dispose or partially dispose of properties based upon a periodic review of our portfolio and the determination by the Board of Directors of BXP that doing so is in our best interests. However, a key component of our current strategic action plan introduced at our September 2025 Investor Day is the execution of a multi-year asset sales program to generate approximately $1.9 billion in net proceeds to fund our development pipeline and reduce leverage. See “ Liquidity and Capital Resources” within “Item 7—Management’s Discussion and Analysis of Financial Condition and Results of Operations” for more details on our asset sales program.

Any decision to dispose of a property or a partial interest in a property will be authorized by the Board of Directors of BXP or a committee thereof. Some holders of limited partnership interests in BPLP could incur adverse tax consequences upon the sale of certain of our properties that differ from the tax consequences to BXP. Consequently, holders of limited partnership interests in BPLP may have different objectives regarding the appropriate pricing and timing of any such sale. Such different tax treatment derives in most cases from the fact that we acquired these properties in exchange for partnership interests in contribution transactions structured to allow the prior owners to defer taxable gain. Generally, this deferral continues so long as we do not dispose of the properties in a taxable transaction. Unless a sale by us of these properties is structured as a like-kind exchange under Section 1031 of the Internal Revenue Code of 1986, as amended (the “Code”), or in a manner that otherwise allows deferral to continue, recognition of the deferred tax gain allocable to these prior owners is generally triggered by a sale. As of December 31, 2025, we had one property that was subject to a tax protection agreement, which may limit our ability to dispose of the asset or require us to pay damages to the prior owner in the event of a taxable

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sale in violation of the agreement. The tax protection agreement expires on December 14, 2033, or earlier upon the occurrence of certain events.

Financing Policies

The agreement of limited partnership of BPLP and BXP’s certificate of incorporation and bylaws do not limit the amount or percentage of indebtedness that we may incur. Further, we do not have a policy limiting the amount of indebtedness that we may incur, nor have we established any limit on the number or amount of mortgages that may be placed on any single property or on our portfolio as a whole. However, our mortgages, credit facilities, joint venture agreements and unsecured debt securities contain customary restrictions, requirements and other limitations on our ability to incur indebtedness. In addition, we evaluate the impact of incremental leverage on our debt metrics and the credit ratings of BPLP’s publicly traded debt. A reduction in BPLP’s credit ratings could result in us borrowing money at higher interest rates.

The Board of Directors of BXP will consider a number of factors when evaluating our level of indebtedness and when making decisions regarding the incurrence of indebtedness, including the purchase price of properties to be acquired with debt financing, the estimated market value of our properties upon refinancing, the cost and effectiveness of entering into interest rate swaps, caps, floors and other interest rate hedging contracts and the ability of particular properties, and us as a whole, to generate cash flow to cover expected debt service.

Policies with Respect to Other Activities

As the sole general partner of BPLP, BXP has the authority to issue additional common and preferred units of limited partnership interest of BPLP. BXP has issued, and may in the future issue, common or preferred units of limited partnership interest to persons who contribute their direct or indirect interests in properties to us in exchange for such common or preferred units. We have not engaged in trading, underwriting or agency distribution or sale of securities of issuers other than BXP and BPLP does not intend to do so. At all times, we intend to make investments in such a manner as to enable BXP to maintain its qualification as a REIT, unless, due to changes in circumstances or to the Code, the Board of Directors of BXP determines that it is no longer in the best interest of BXP to qualify as a REIT. We may make loans to third parties, including, without limitation, to joint ventures in which we participate or in connection with the disposition of a property. We intend to make investments in such a way that we will not be treated as an investment company under the 1940 Act. Our policies with respect to these and other activities may be reviewed and modified or amended from time to time by the Board of Directors of BXP.

Governmental Regulations

General

Compliance with various governmental regulations has an impact on our business, including our capital expenditures, earnings and competitive position, which can be material. We incur costs to monitor and take actions to comply with governmental regulations that are applicable to our business, which include, among others, (1) federal securities laws and regulations, (2) applicable stock exchange requirements, and (3) federal, state and local laws and regulations related to (a) our status as a REIT and other tax laws and regulations, and (b) real property, the improvements thereon and the operation thereof, such as laws and regulations relating to the environment, health and safety, zoning, usage, building, fire and life safety codes, (4) the requirements of the Office of Foreign Assets Control of the United States Department of the Treasury and (5) the Americans with Disabilities Act of 1990. In addition to the discussion below, see “ Item 1A. – Risk Factors ” for a discussion of these governmental regulations and other material risks to us, including, to the extent material, to our competitive position, and see “ Item 7— Management’s Discussion and Analysis of Financial Condition and Results of Operations ” together with our consolidated financial statements, including the related notes included therein, for a discussion of material information relevant to an assessment of our financial condition and results of operations, including, to the extent material, the effects that compliance with governmental regulations may have upon our capital expenditures and earnings.

Environmental Matters

It is our policy to retain independent environmental consultants to conduct or update Phase I environmental assessments (which generally do not involve invasive techniques such as soil or ground water sampling) and asbestos surveys in connection with our acquisition of properties. These pre-purchase environmental assessments have not revealed environmental conditions that we believe will have a material adverse effect on our business, assets, financial condition, results of operations or liquidity, and we are not otherwise aware of environmental

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conditions with respect to our properties that we believe would have such a material adverse effect. However, from time to time environmental conditions at our properties have required and may in the future require environmental testing and/or regulatory filings, as well as remedial action.

For example, in February 1999, we (through a joint venture) acquired from Exxon Corporation a property in Massachusetts that was formerly used as a petroleum bulk storage and distribution facility and was known by the state regulatory authority to contain soil and groundwater contamination. We developed an office park on the property. We engaged a specially licensed environmental consultant to oversee the management of contaminated soil and groundwater that was disturbed in the course of construction. Under the property acquisition agreement, Exxon agreed to (1) bear the liability arising from releases or discharges of oil and hazardous substances which occurred at the site prior to our ownership, (2) continue monitoring and/or remediating such releases and discharges as necessary and appropriate to comply with applicable requirements, and (3) indemnify us for certain losses arising from preexisting site conditions. Any indemnity claim may be subject to various defenses and contractual limitations, including time limits and limits on the specific use of the property, and there can be no assurance that the amounts paid under the indemnity, if any, would be sufficient to cover the liabilities arising from any such releases and discharges.

Environmental investigations at some of our properties and certain properties owned by our affiliates have identified groundwater contamination migrating from off-site source properties. In each case we engaged a licensed environmental consultant to perform the necessary investigations and assessments, and to prepare any required submittals to the regulatory authorities. In each case the environmental consultant concluded that the properties qualify under the regulatory program or the regulatory practice for a status which eliminates certain deadlines for conducting response actions at a site. We also believe that these properties qualify for liability relief under certain statutory provisions or regulatory practices regarding upgradient releases. Although we believe that the current or former owners of the upgradient source properties may bear responsibility for some or all of the costs of addressing the identified groundwater contamination, we will take such further response actions (if any) that we deem necessary or advisable. Other than periodic testing at some of these properties, no such additional response actions are anticipated at this time.

Some of our properties and certain properties owned by our affiliates are located in urban, industrial and other previously developed areas where fill or current or historical use of the areas have caused site contamination. Accordingly, it is sometimes necessary to institute special soil and/or groundwater handling procedures and/or include particular building design features in connection with development, construction and other property operations in order to achieve regulatory closure and/or ensure that contaminated materials are addressed in an appropriate manner. In these situations, it is our practice to investigate the nature and extent of detected contamination, including potential issues associated with vapor intrusion concerns and/or potential contaminant migration to or from the subject property in ground water, assess potential liability risks and estimate the costs of required response actions and special handling procedures. We then use this information as part of our decision-making process with respect to the acquisition, deal structure and/or development of the property. For example, we own a parcel in Massachusetts which was formerly used as a quarry/asphalt batching facility. Pre-purchase testing indicated that the site contained relatively low levels of certain contaminants. We have developed an office park on this property. Prior to and during redevelopment activities, we engaged a specially licensed environmental consultant to monitor environmental conditions at the site and prepare necessary regulatory submittals based on the results of an environmental risk characterization. A submittal has been made to the regulatory authorities in order to achieve regulatory closure at this site. The submittal included an environmental deed restriction that mandates compliance with certain protective measures in a portion of the site where low levels of residual soil contamination have been left in place in accordance with applicable laws.

We expect that resolution of the environmental matters described above will not have a material impact on our business, assets, financial condition, results of operations or liquidity. However, we cannot assure you that we have identified all environmental liabilities at our properties, that all necessary remediation actions have been or will be undertaken at our properties, that we will be indemnified, in full or at all, or that we will have insurance coverage in the event that such environmental liabilities arise.

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Corporate Governance

BXP is currently governed by an eleven-member Board of Directors. The current members of the Board of Directors of BXP are Bruce W. Duncan, Diane J. Hoskins, Mary E. Kipp, Joel I. Klein, Douglas T. Linde, Matthew J. Lustig, Timothy J. Naughton, Julie G. Richardson, Owen D. Thomas, William H. Walton III, and Derek A. (Tony) West. All directors of BXP’s Board of Directors stand for election for one-year terms expiring at the next succeeding annual meeting of stockholders.

Owen D. Thomas currently serves as the Chairman of BXP’s Board of Directors and Joel I. Klein serves as its Lead Independent Director. The Board of Directors of BXP also has Audit, Compensation, Nominating and Corporate Governance and Sustainability Committees. The membership of each of these committees is set forth below.

Audit

Compensation

Nominating and

Corporate Governance

Sustainability

Bruce W. Duncan

Diane J. Hoskins

Mary E. Kipp

Joel I. Klein (2)

Douglas T. Linde

Matthew J. Lustig

Timothy J. Naughton

Julie G. Richardson

Owen D. Thomas (3)

William H. Walton III

Derek A. (Tony) West

X=Committee member, (1)=Committee Chair, (2)=Lead Independent Director, (3)=Chairman of BXP’s Board of Directors

BXP has the following corporate governance documents and procedures in place:

• The Board of Directors has adopted charters for each of its Audit, Compensation and Nominating and Corporate Governance Committees. A copy of each of these charters is available on our website at http://www.bxp.com under the heading “Investors” and subheading “Governance.”

• The Board of Directors has adopted Corporate Governance Guidelines, a copy of which is available on our website at http://www.bxp.com under the heading “Investors” and subheading “Governance” with the n ame “Governance Guidelines.”

• The Board of Directors has adopted a Code of Business Conduct and Ethics, which governs business decisions made and actions taken by BXP’s directors, officers and employees. A copy of this code is available on our website at http://www.bxp.com under the heading “Investors” and subheading “Governance” with the n ame “Code of Business Conduct and Ethics.” BXP intends to disclose on this website any amendment to, or waiver of, any provisions of this Code applicable to the directors and executive officers of BXP that would otherwise be required to be disclosed under the rules of the SEC or the New York Stock Exchange.

• The Board of Directors has established an ethics reporting system that employees may use to anonymously report possible violations of the Code of Business Conduct and Ethics, including concerns regarding questionable accounting, internal accounting controls or auditing matters, by telephone or over the internet.

• The Board of Directors has adopted a Policy on Political Spending, a copy of which is available on our website at http://www.bxp.com under the heading “Investors” and the subheading “Governance” with the name “Policy on Political Spending.” We disclose all political spending on our website and update such disclosures biannually.

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Competition

We compete in the leasing of premier workplace, retail and residential space with a considerable number of other real estate companies, some of which may have greater marketing and financial resources than are available to us. In addition, our hotel property competes for guests with other hotels, some of which may have greater marketing and financial resources than are available to us and to the manager of our one hotel, Marriott International, Inc.

Principal factors of competition in our primary business of owning, acquiring and developing premier workplaces are the quality of properties, leasing terms (including rent and other charges and allowances for tenant improvements), attractiveness and convenience of location, the quality and breadth of client services and amenities provided, and reputation as an owner and operator of premier workplaces in the relevant market. Additionally, our ability to compete depends upon, among other factors, trends in the national and local economies, investment alternatives, financial condition and operating results of current and prospective clients, availability and cost of capital, construction and renovation costs, taxes, utilities, governmental regulations, legislation and population trends.

In addition, at December 31, 2025, we had seven residential properties (including three under construction) and may in the future decide to acquire or develop additional residential properties. As an owner, we will also face competition for prospective residents from other operators/owners whose properties may be perceived to offer a better location or better amenities or whose rent may be perceived as a better value given the quality, location and amenities that the resident seeks. We will also compete against condominiums and single-family homes that are for sale or rent. Because the scale of our residential portfolio is relatively small, we expect to continue to retain third parties to manage our residential properties.

Our Hotel Property

We operate our hotel property through a taxable REIT subsidiary. The taxable REIT subsidiary, a wholly-owned subsidiary of BPLP, is the lessee pursuant to a lease for the hotel property. As lessor, BPLP is entitled to a percentage of gross receipts from the hotel property. The hotel lease is intended to provide the economic benefits of ownership of the underlying real estate to flow to us as rental income, while our taxable REIT subsidiary earns the profit or loss from operating the property as a hotel. Marriott International, Inc. continues to manage the hotel property under the Marriott name and under terms of the existing management agreements. Marriott has been engaged under a separate long-term incentive management agreement to operate and manage the hotel on behalf of the taxable REIT subsidiary.

Supplemental United States Federal Income Tax Considerations

The following discussion supplements and updates the disclosures under the heading “United States Federal Income Tax Considerations” in the prospectus dated May 17, 2023, contained in our Registration Statements on Form S-3 (File Nos. 333-272012, 333-272012-01) filed with the Securities and Exchange Commission on May 17, 2023 (the “Existing Tax Disclosure”). Capitalized terms herein that are not otherwise defined shall have the same meaning as when used in the Existing Tax Disclosure.

On July 4, 2025, the One Big Beautiful Bill Act (the “OBBB”), was enacted. The OBBB makes major changes to the Code, including some provisions of the Code that affect the taxation of REITs and their investors. In particular,

• For taxable years beginning on or after January 1, 2026, the OBBB relaxed the REIT asset test requirement with respect to taxable REIT subsidiaries, providing that not more than 25% (relaxed from 20%) of the gross value of a REIT’s assets may be represented by securities of one or more taxable REIT subsidiaries.

• The OBBB permanently extended the pass-through qualified business income deduction, generally allowing individuals to deduct 20% of the aggregate amount of ordinary REIT dividends distributed by a REIT. This deduction was due to expire for tax years beginning after December 31, 2025.

• The OBBB provides that the highest individual marginal tax rate will not revert from 37% to 39.6% for taxable years beginning after December 31, 2025. The 37% rate is made permanent.

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To the extent the information set forth in the Existing Tax Disclosure is inconsistent with this supplemental information, this supplemental information supersedes the information in the Existing Tax Disclosure. This supplemental information is provided on the same basis and subject to the same qualifications as are set forth in the first four paragraphs of the Existing Tax Disclosure as if those paragraphs were set forth in this Annual Report on Form 10-K.

Item 1A. Risk Factors.

Set forth below are the risks that we believe are material to our investors and they should be carefully considered. Throughout this section, we refer to the equity and debt securities of both BXP and BPLP as our “securities,” and the investors who own securities of BXP, BPLP or both, as our “securityholders.” These risks are not all of the risks we face and other factors not presently known to us or that we currently believe are immaterial may also affect our business if they occur. This section contains forward-looking statements. You should refer to the explanation of the qualifications and limitations on forward-looking statements beginning on page 52 .

Risks Related to Our Business and Operations

Our performance depends upon the economic conditions, particularly the supply and demand characteristics, of our markets—Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC.

Substantially all of our revenue is derived from properties located in six markets: Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC. A downturn in the economies of these markets, or the impact that a downturn in the overall national economy may have upon these economies, could result in reduced demand for office space and/or a reduction in rents. Because our portfolio consists primarily of premier workplace buildings (as compared to a more diversified real estate portfolio), a decrease in demand for workplaces in turn could adversely affect our results of operations. Additionally, there are submarkets within our markets that are dependent upon a limited number of industries. For example, in our Washington, DC market, we focus on leasing our properties to governmental contractors and legal firms. In our West Coast markets, our leasing is focused on clients in the technology and media industries, as well as legal firms. In addition, in our New York market, we have historically leased properties to financial, legal and other professional firms. A reduction in spending by the Federal Government, sustained changes in space utilization due to remote work models and/or changes from workforce reductions due to artificial intelligence, and/or a significant downturn in one or more of the foregoing sectors have resulted in, and could continue to result in, reduced demand for office space and adversely affect our results of operations.

In addition, a significant economic downturn over a period of time could result in an event or change in circumstances that results in an impairment of a long-lived asset or an “other than temporary” impairment in the value of our investments in unconsolidated joint ventures. For the year ended December 31, 2025, BXP and BPLP recognized impairments of long-lived assets of approximately $85.8 million and $82.9 million, respectively, and one of our investments in an unconsolidated joint venture recognized an “other than temporary” impairment of approximately $145.1 million. For additional information on these impairments, see Notes 3 and 6 to the Consolidated Financial Statements. Any future impairments could have a material adverse effect on our results of operations in the period in which the charge is taken.

Market and economic volatility due to adverse economic and political conditions, health crises or dislocations in the credit markets could have a material adverse effect on our results of operations, financial condition and ability to pay dividends and/or distributions.

Our business may be adversely affected by market and economic volatility experienced by the U.S. and global economies, the real estate industry as a whole and/or the local economic conditions in the markets in which our properties are located. Such adverse economic and political conditions may include, among other issues, inflation, elevated interest rates, policy changes, prolonged labor market challenges impacting the recruitment and retention of talent, volatility in the public equity and debt markets, and international economic and other conditions, including pandemics, geopolitical instability and other conditions beyond our control. These current conditions, or similar conditions existing in the future, may adversely affect our results of operations, financial condition and ability to pay dividends and distributions as a result of the following, among other potential consequences:

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• federal policy changes, such as the implementation of tariffs that have resulted in, and may continue to result in, global supply chain disruptions and/or sustained inflation, could negatively impact interest rates, potential changes to U.S. federal tax laws and budgetary changes related to government leases;

• the financial condition of our clients may be adversely affected, which may result in client defaults under leases due to bankruptcy, lack of liquidity, lack of funding, operational failures or for other reasons;

• significant job losses and/or a sustained shift away from collective in-person work environments or relocations away from the markets in which we operate may occur, which could decrease overall demand for workplaces in the regions in which we operate and cause market rental rates and property values to be negatively impacted;

• our inability to borrow on terms and conditions that we find acceptable, or at all, which could reduce our ability to pursue acquisition and development opportunities and refinance existing debt, reduce our returns from our acquisition and development activities and increase our future interest expense;

• reduced values of our properties may limit our ability to dispose of assets at attractive prices or to obtain debt financing secured by our properties and may reduce the availability of unsecured loans;

• the value and liquidity of our short-term investments and cash deposits could be reduced as a result of a deterioration of the financial condition of the institutions that hold our cash deposits or the institutions or assets in which we have made short-term investments, a dislocation of the markets for our short-term investments, increased volatility in market rates for such investments or other factors;

• one or more lenders under our line of credit could refuse to fund their financing commitment to us or could fail, and we may not be able to replace the financing commitment of any such lenders on favorable terms, or at all; and

• one or more counterparties to our derivative financial instruments could default on their obligations to us, or could fail, increasing the risk that we may not realize the benefits of these instruments. For example, in connection with our offering of 2.00% Exchangeable Senior Notes due 2030 in September 2025, we entered into capped call transactions with certain option counterparties. The option counterparties are financial institutions, and we are subject to the risk that any or all of them might default under the capped call transactions. Our exposure to the credit risk of the option counterparties is not secured by any collateral. Further, global economic conditions have resulted in the actual or perceived failure or financial difficulties of certain financial institutions and could adversely impact the option counterparties’ performance under the capped call transactions. We can provide no assurances as to the financial stability or viability of the option counterparties.

Our success depends on key personnel whose continued service is not guaranteed.

We depend on the efforts of key personnel, particularly Owen D. Thomas, Chief Executive Officer, Douglas T. Linde, President and Michael E. LaBelle, Executive Vice President, Chief Financial Officer & Treasurer. Among the reasons that Messrs. Thomas, Linde and LaBelle are important to our success is that each has a national reputation, which attracts business and investment opportunities and assists us in negotiations with lenders, joint venture partners and other investors. If we lost their services, our relationships with lenders, potential clients and industry personnel could diminish.

Our Regional Managers also have strong reputations. Their reputations aid us in identifying opportunities, having opportunities brought to us, and negotiating with clients and build-to-suit prospects. While we believe that we could find replacements for these key personnel, the loss of their services could materially and adversely affect our operations because of diminished relationships with lenders, prospective clients and industry personnel.

Risks Related to Real Estate

Our performance and value are subject to risks associated with our real estate assets and with the real estate industry.

Our economic performance and the value of our real estate assets, and consequently the value of our securities, are subject to the risk that if our properties do not generate revenues sufficient to meet our operating expenses, including debt service and capital expenditures, our cash flow and ability to pay distributions to our

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securityholders will be adversely affected. The following factors, among others, may adversely affect the income generated by our properties:

• downturns in the national, regional and local economic conditions (particularly increases in unemployment);

• sustained changes in client preferences and space utilization from full-time, collective in-person work environments to hybrid or remote work models and/or changes from workforce reductions due to artificial intelligence, which could decrease overall demand for workplaces and negatively impact market rental rates and property values;

• competition from other office, life sciences, hotel, retail and residential buildings;

• local real estate market conditions, such as oversupply or reduction in demand for office, life sciences, hotel, retail or residential space;

• changes in interest rates and availability of financing;

• vacancies, changes in market rental rates and the need to periodically repair, renovate and re-let space;

• delays in completion of development and redevelopment projects due to supply chain disruptions and labor shortages;

• increased costs to maintain, renovate and develop our properties related to inflation;

• increased operating costs, including insurance expense, utilities, real estate taxes, state and local taxes and heightened security costs;

• civil disturbances, earthquakes and other natural disasters or terrorist acts or acts of war which may result in uninsured or underinsured losses or decrease the desirability of our properties to our clients in impacted locations;

• significant expenditures associated with each investment, such as debt service payments, real estate taxes (including reassessments and changes in tax laws), insurance and maintenance costs which are generally not reduced when circumstances cause a reduction in revenues from a property;

• declines in the financial condition of our clients and our ability to collect rents from our clients; and

• decreases in the underlying value of our real estate.

We face potential adverse effects from major clients’ bankruptcies or insolvencies.

The bankruptcy or insolvency of a major client may adversely affect the income produced by our properties. Our clients could file for bankruptcy protection or become insolvent in the future. We cannot evict a client solely because of its bankruptcy. On the other hand, a bankrupt client may reject and terminate its lease with us. In such case, our claim against the bankrupt client for unpaid and future rent would be subject to a statutory cap that might be substantially less than the remaining rent actually owed under the lease, and, even so, our claim for unpaid rent would likely not be paid in full. This shortfall could adversely affect our cash flow and results of operations.

Our properties face significant competition.

We face significant competition from developers, owners and managers of office, life sciences and residential properties and other commercial real estate, including sublease space available from our clients. Substantially all of our properties face competition from similar properties in the same market. This competition may affect our ability to attract and retain clients and may reduce the rents we are able to charge. These competing properties may have vacancy rates higher than our properties, which may result in their owners being willing to lease available space at lower rates than the space in our properties.

We face potential difficulties or delays renewing leases or re-leasing space.

We derive most of our income from rent received from our clients. If a client experiences a downturn in its business or other types of financial distress, it may be unable to make timely rental payments. Also, when our clients decide not to renew their leases, renew for less space or terminate early, we may not be able to re-let the space or there could be a substantial delay in re-letting the space. Even if clients decide to renew or lease new

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space, the terms of renewals or new leases, including the cost of required renovations or concessions to clients, may be less favorable to us than current lease terms. As a result, our cash flow could decrease and our ability to make distributions to our securityholders could be adversely affected.

Our actual costs to develop properties may exceed our budgeted costs.

We intend to continue to develop and substantially renovate office, life sciences, retail and residential properties. Our current and future development and construction activities may be exposed to the following risks:

• we may be unable to proceed with the development of properties because we cannot obtain financing on favorable terms or at all;

• we may incur construction costs for a development project that exceed our original estimates due to increased materials, labor, leasing or other costs, increases in interest rates, or supply chain disruptions, any of which could make completion of the project less profitable because market rents may not increase sufficiently to compensate for the increase in construction costs;

• we may be unable to obtain, or face delays in obtaining, required zoning, land-use, building, occupancy, and other governmental permits and authorizations, which could result in increased costs and could require us to abandon our activities entirely with respect to a project;

• we may abandon development opportunities after we begin to explore them and, as a result, we may lose deposits or fail to recover expenses already incurred;

• we may expend funds on and devote management’s time to projects that we do not complete;

• we may be unable to complete construction and/or leasing of a property on schedule or at all; and

• we may suspend development projects after construction has begun due to changes in economic conditions or other factors, and this may result in the write-off of costs, payment of additional costs or increases in overall costs when the development project is restarted.

Investment returns from our developed properties may be less than anticipated.

Our developed properties may be exposed to the following risks:

• we may lease developed properties at rental rates that are less than projected, or at a slower pace than projected, at the time we decide to undertake the development;

• operating expenses and construction costs may be greater than projected at the time of development, resulting in our investment being less profitable than we expected; and

• occupancy rates and rents at newly developed properties may fluctuate depending on a number of factors, including market and economic conditions, and may result in our investments being less profitable than we expected or not profitable at all.

We face risks associated with the development of mixed-use commercial and residential properties.

We operate, are currently developing, and may in the future develop, properties either alone or through joint ventures with other parties that are known as “mixed-use” properties. For mixed-use developments, this means that in addition to the development of office space, the project may also include space for residential, retail, hotel or other commercial purposes. We are also developing, and may in the future develop, residential buildings. We have less experience in developing and managing non-office and non-retail real estate than we do with office real estate. As a result, if a development project includes a non-office or non-retail use, we may seek to develop that component ourselves, sell the rights to that component to a third-party developer with experience in that use or we may seek to partner with such a developer. If we do not sell the rights or partner with such a developer, or if we choose to develop the other component ourselves, we would be exposed not only to those risks typically associated with the development of commercial real estate generally, but also to specific risks associated with the development and ownership of non-office and non-retail real estate. In addition, even if we sell the rights to develop the other component or elect to participate in the development through a joint venture, we may be exposed to the risks associated with the failure of the other party to complete the development as expected. These include the risk that the other party would default on its obligations necessitating that we complete the other component ourselves (including providing any necessary financing). In the case of residential properties, these risks include competition

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for prospective residents from other operators whose properties may be perceived to offer a better location or better amenities or whose rent may be perceived as a better value given the quality, location and amenities that the resident seeks. We will also compete against condominiums and single-family homes that are for sale or rent. Because we have less experience with residential properties than with office and retail properties, we retain third parties to manage our residential properties. When we hire a third-party manager, we are dependent on them and their key personnel who provide services to us and we may not find a suitable replacement if the management agreement is terminated, or if key personnel leave or otherwise become unavailable to us.

Our use of joint ventures may limit our control over jointly owned investments and limit our flexibility to acquire other assets.

In appropriate circumstances, we intend to acquire and recapitalize or develop, as applicable, properties in joint ventures with other parties. We currently have joint ventures that are and are not consolidated within our financial statements. Our participation in joint ventures subjects us to risks, including but not limited to, the following risks that:

• our joint venture partners may have different objectives than we have regarding the appropriate timing and terms of any sale or refinancing of a property, its operation or, if applicable, the commencement of development activities, and a dispute with any of our joint venture partners could lead to the sale of a partner’s ownership interest in the venture or the property at a time or price that we do not find attractive;

• some of our joint ventures are subject to debt and, depending on credit market conditions, the refinancing of such debt may require equity capital calls;

• our joint venture partners may be structured differently than us for tax purposes and this could create conflicts of interest, including with respect to our compliance with the REIT requirements, and our REIT status could be jeopardized if any of our joint ventures do not operate in compliance with REIT requirements;

• our joint venture partners may have competing interests in our markets that could create conflicts of interest;

• our joint venture partners may default on their obligations, which could necessitate that we fulfill their obligations ourselves;

• our joint ventures may be unable to repay any amounts that we may loan to them;

• our joint venture agreements may contain provisions limiting the liquidity of our interest for sale or sale of the entire asset;

• as the general partner or managing member of a joint venture, we could be generally liable under applicable law for the debts and obligations of the venture, and we may not be entitled to contribution or indemnification from our partners;

• our joint venture agreements may contain provisions that allow our partners to remove us as the general partner or managing member for cause, and this could result in liability for us to our partners under the governing agreement of the joint venture; and

• we may need our partner(s)’ approval to take certain actions and, therefore, we may be unable to cause a joint venture to implement decisions that we consider advisable.

We face the risk that third parties will not be able to service or repay loans we make to them.

From time to time, we have loaned and in the future may loan funds to (1) a third-party buyer to facilitate the sale of an asset by us to such third party, or (2) a third party in connection with the formation of a joint venture to acquire and/or develop a property. Making these loans subjects us to the following risks, each of which could have a material adverse effect on our cash flow, results of operations and/or financial condition:

• the third party may be unable to make full and timely payments of interest and principal on the loan when due;

• if the third-party buyer to whom we provide seller financing does not manage the property well, or the property otherwise fails to meet financial projections, performs poorly or declines in value, then the buyer

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may not have the funds or ability to raise new debt with which to make required payments of interest and principal to us;

• if we loan funds to a joint venture, and the joint venture is unable to make required payments of interest or principal, or both, or there are disagreements with respect to the repayment of the loan or other matters, then we could have a resulting dispute with our partner(s), and such a dispute could harm our relationship(s) with our partner(s) and cause delays in developing or selling the property or the failure to properly manage the property; and

• if we loan funds to a joint venture and the joint venture is unable to make required payments of interest and principal, or both, then we may exercise remedies available to us in the joint venture agreement that could allow us to increase our ownership interest or our control over major decisions, or both, which could result in an unconsolidated joint venture becoming consolidated with our financial statement; doing so could require us to reallocate the purchase price among the various asset and liability components and this could result in material changes to our reported results of operations and financial condition.

We face risks associated with property acquisitions.

We have acquired in the past and intend to continue to pursue the acquisition of properties and portfolios of properties, including large portfolios that could increase our size and result in alterations to our capital structure. Our acquisition activities and their success are subject to the following risks:

• even if we enter into an acquisition agreement for a property, we may be unable to complete that acquisition after making a non-refundable deposit and incurring certain other acquisition-related costs;

• we may be unable to obtain or assume financing for acquisitions on favorable terms or at all;

• acquired properties may fail to perform as expected;

• the actual costs of repositioning, redeveloping or maintaining acquired properties may be greater than our estimates;

• the acquisition agreement will likely contain conditions to closing, including completion of due diligence investigations to our satisfaction or other conditions that are not within our control, which may not be satisfied;

• acquired properties may be located in new markets, either within or outside the United States, where we may face risks associated with a lack of market knowledge or understanding of the local economy, lack of business relationships in the area, costs associated with opening a new regional office and unfamiliarity with local governmental and permitting procedures;

• we may acquire real estate through the acquisition of the ownership entity subjecting us to the risks of that entity; and

• we may be unable to quickly and efficiently integrate new acquisitions, particularly acquisitions of portfolios of properties, into our existing operations, and this could have an adverse effect on our results of operations and financial condition.

We have acquired in the past and in the future may acquire properties through the acquisition of first mortgage or mezzanine debt. Investments in these loans must be carefully structured to ensure that BXP continues to satisfy the various asset and income requirements applicable to REITs. If we fail to properly structure any such acquisition, BXP could fail to qualify as a REIT. In addition, acquisitions of first mortgage or mezzanine loans subject us to the risks associated with the borrower’s default, including potential bankruptcy, and there may be significant delays and costs associated with the process of foreclosure on collateral securing or supporting these investments.  There can be no assurance that we would recover any or all of our investment in the event of such a default or bankruptcy.

We have acquired in the past and in the future may acquire properties or portfolios of properties through tax deferred contribution transactions in exchange for partnership interests in BPLP. Among other things, this acquisition structure has the effect of reducing the amount of tax depreciation we can deduct over the tax life of the acquired properties, and it typically requires that we agree to protect the contributors’ ability to defer recognition of taxable gain through restrictions on our ability to dispose of the acquired properties and/or the allocation of partnership debt to the contributors to maintain their tax bases. These restrictions could limit our ability to sell an asset at a time, or on terms, that would be favorable absent such restrictions.

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Acquired properties may expose us to unknown liability.

We may acquire properties or invest in joint ventures that own properties subject to liabilities and without any recourse, or with only limited recourse, against the prior owners or other third parties with respect to unknown liabilities. As a result, if a liability were asserted against us based upon ownership of those properties, we might have to pay substantial sums to settle or contest it, which could adversely affect our results of operations and cash flow. Unknown liabilities with respect to acquired properties might include:

• liabilities for clean-up of undisclosed environmental contamination;

• claims by clients, vendors or other persons against the former owners of the properties;

• liabilities incurred in the ordinary course of business; and

• claims for indemnification by general partners, directors, officers and others indemnified by the former owners of the properties.

Competition for acquisitions may result in increased prices for properties.

We plan to continue to acquire properties as we are presented with attractive opportunities. We may face competition for acquisition opportunities with other investors, and this competition may adversely affect us by subjecting us to the following risks:

• we may be unable to acquire a desired property because of competition from other well-capitalized real estate investors, including publicly traded and private REITs, institutional investment funds and other real estate investors; and

• even if we are able to acquire a desired property, competition from other real estate investors may significantly increase the purchase price.

We may have difficulty selling our properties, which may limit our flexibility.

Properties like the ones that we own could be difficult to sell due to adverse economic conditions, a lack of available buyers and other conditions outside of our control. This may limit our ability to change our portfolio promptly in response to changes in economic or other conditions or to execute on our multi-year asset sales program. Any such inability to dispose of certain assets on the timelines we anticipate or on terms that are favorable to us, or at all, could negatively impact the proceeds we expect the multi-year asset sales program to generate, and accordingly, could adversely affect our financial condition and results of operations.

In addition, federal tax laws limit our ability to sell properties, which may affect our ability to sell properties without adversely affecting returns to our securityholders and our ability to dispose of certain of our properties is further constrained by their tax attributes. Properties that we developed and have owned for a significant period of time or that we acquired through tax deferred contribution transactions in exchange for partnership interests in BPLP often have low tax bases. Furthermore, as a REIT, BXP may be subject to a 100% “prohibited transactions” tax on the gain from dispositions of property if BXP is deemed to hold the property primarily for sale to customers in the ordinary course of business, unless the disposition qualifies under a safe harbor exception for properties that have been held for at least two years and with respect to which certain other requirements are met. The potential application of the prohibited transactions tax could cause us to forego potential dispositions of property or other opportunities that might otherwise be attractive to us, or to undertake such dispositions or other opportunities through a taxable REIT subsidiary, which would generally result in income taxes being incurred. If we dispose of these properties outright in taxable transactions, we may be required to distribute a significant amount of the taxable gain to our securityholders under the requirements of the Code applicable to REITs, which in turn would impact our future cash flow and may increase our leverage. In some cases, without incurring additional costs we may be restricted from disposing of properties contributed in exchange for our partnership interests under tax protection agreements with contributors. To dispose of low basis or taxprotected properties efficiently we from time to time use like-kind exchanges, which are intended to qualify for nonrecognition of taxable gain, but can be difficult to consummate and result in the property for which the disposed assets are exchanged inheriting their low tax bases and other tax attributes (including tax protection covenants).

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Because we own a hotel property, we face the risks associated with the hospitality industry.

The following factors, among others, are common to the hotel industry, and may reduce the receipts generated by our hotel property:

• our hotel property competes for guests with other hotels, a number of which may have greater marketing and financial resources than our hotel-operating business partners;

• if there is an increase in operating costs resulting from inflation and other factors, our hotel-operating business partners may not be able to offset such increase by increasing room rates;

• our hotel property is subject to the fluctuating and seasonal demands of business travelers and tourism; and

• our hotel property is subject to general and local economic and social conditions that may affect demand for travel in general, including fluctuations in consumer spending, public health concerns, war and terrorism.

In addition, because our hotel property is located in Cambridge, Massachusetts, it is subject to the Cambridge market’s fluctuations in demand, increases in operating costs and increased competition from additions in supply.

Failure to comply with Federal Government contractor requirements could result in substantial costs and loss of substantial revenue.

As of December 31, 2025, the U.S. Government was one of our clients and we are subject to compliance with a wide variety of complex legal requirements because we are a Federal Government contractor. These laws regulate how we conduct business, require us to administer various compliance programs and require us to impose compliance responsibilities on some of our contractors. Our failure to comply with these laws could subject us to fines, penalties and damages, cause us to be in default of our leases and other contracts with the Federal Government and bar us from entering into future leases and other contracts with the Federal Government. There can be no assurance that these costs and loss of revenue will not have a material adverse effect on our properties, operations or business.

Changes in rent control or rent stabilization and eviction laws and regulations in our markets could have a material adverse effect on our residential portfolio’s results of operations and residential property values.

Various state and local governments have enacted, and may continue to enact, rent control or rent stabilization laws and regulations or take other actions that could limit our ability to raise rents or charge certain fees, such as pet fees or application fees. Depending on the extent and terms of future enactments of rent control or rent stabilization laws and regulations, as well as any lawsuits against us arising from such issues, such future enactments could have a material adverse effect on our residential portfolio’s results of operations and the value of our residential properties.

State and local governments may also make changes to eviction and other tenants’ rights laws and regulations that could have a material adverse effect on our residential portfolio’s results of operations and the value of our residential properties. If we are restricted from re-leasing apartment units due to the inability to evict delinquent residents, our results of operations and property values for our residential properties may be adversely affected.

We did not obtain new owner’s title insurance policies in connection with properties acquired during BXP’s initial public offering.

We acquired many of our properties from our predecessors at the completion of BXP’s initial public offering in June 1997. Before we acquired these properties, each of them was insured by a title insurance policy. We did not obtain new owner’s title insurance policies in connection with the acquisition of these properties. To the extent we have financed properties after acquiring them in connection with the initial public offering, we have obtained new title insurance policies, however, the amount of these policies may be less than the current or future value of the applicable properties. Nevertheless, because in many instances we acquired these properties indirectly by acquiring ownership of the entity that owned the property and those owners remain in existence as our subsidiaries, some of these title insurance policies may continue to benefit us. Many of these title insurance policies may be for amounts less than the current or future values of the applicable properties. If there was a title defect related to any of these properties, or to any of the properties acquired at the time of the initial public offering of BXP, that is no

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longer covered by a title insurance policy, we could lose both our capital invested in and our anticipated profits from such property. We have obtained title insurance policies for all properties that we have acquired after the initial public offering of BXP, however, these policies may be for amounts less than the current or future values of the applicable properties.

Some potential losses are not covered by insurance.

Our property insurance program per occurrence limits are $1.0 billion for our portfolio insurance program, including coverage for acts of terrorism other than nuclear, biological, chemical or radiological terrorism (“Terrorism Coverage”). We also carry $1.35 billion of property insurance in excess of the $1.0 billion of coverage in our property insurance program for 601 Lexington Avenue, New York, New York, consisting of $750 million of property and Terrorism Coverage in excess of our property insurance program and $600 million of Terrorism Coverage only in excess of the $1.75 billion of coverage. Certain properties, including the General Motors Building located at 767 Fifth Avenue in New York, New York (“767 Fifth Avenue”), are currently insured in separate insurance programs. The property insurance program per occurrence limits for 767 Fifth Avenue are $1.625 billion, including Terrorism Coverage. We also currently carry nuclear, biological, chemical and radiological terrorism insurance coverage for acts of terrorism certified under the Federal Terrorism Risk Insurance Act (as amended, “TRIA”) (“NBCR Coverage”), which is provided by IXP, LLC (“IXP”) as a direct insurer, for the properties in our portfolio, including 767 Fifth Avenue, but excluding certain other properties owned in joint ventures with third parties or which we manage. The per occurrence limit for NBCR Coverage is $1.0 billion. Under TRIA, after the payment of the required deductible and coinsurance, the NBCR Coverage provided by IXP is backstopped by the Federal Government if the aggregate industry insured losses resulting from a certified act of terrorism exceed a “program trigger.” The program trigger is $200 million, the coinsurance is 20% and the deductible is 20% of the premiums earned by the insurer for the year prior to a claim. If the Federal Government pays out for a loss under TRIA, it is mandatory that the Federal Government recoup the full amount of the loss from insurers offering TRIA coverage after the payment of the loss pursuant to a formula in TRIA. We may elect to terminate the NBCR Coverage if the Federal Government seeks recoupment for losses paid under TRIA, if TRIA is not extended after its expiration on December 31, 2027, if there is a change in our portfolio or for any other reason. We intend to continue to monitor the scope, nature and cost of available terrorism insurance.

We also currently carry earthquake insurance on our properties located in areas known to be subject to earthquakes. Specifically, we currently carry earthquake insurance which covers our San Francisco and Los Angeles regions with a $330 million per occurrence limit, and a $330 million annual aggregate limit, $30 million of which is provided by IXP, as a direct insurer. This insurance is subject to a deductible in the amount of 5% of the value of the affected property. In addition, we currently carry earthquake insurance which covers our Seattle region with a $110 million per occurrence limit, and a $110 million annual aggregate limit. This insurance is subject to a deductible in the amount of 2% of the value of the affected property. The amount of our earthquake insurance coverage may not be sufficient to cover losses from earthquakes. In addition, the amount of earthquake coverage could impact our ability to finance properties subject to earthquake risk. We may discontinue earthquake insurance or change the structure of our earthquake insurance program on some or all of our properties in the future if the premiums exceed our estimation of the value of the coverage.

IXP, a captive insurance company which is a wholly-owned subsidiary, acts as a direct insurer with respect to a portion of our earthquake insurance coverage for our Greater San Francisco and Los Angeles properties and our NBCR Coverage. Insofar as we own IXP, we are responsible for its liquidity and capital resources, and the accounts of IXP are part of our consolidated financial statements. In particular, if a loss occurs which is covered by our NBCR Coverage but is less than the applicable program trigger under TRIA, IXP would be responsible for the full amount of the loss without any backstop by the Federal Government. IXP would also be responsible for any recoupment charges by the Federal Government in the event losses are paid out and its insurance policy is maintained after the payout by the Federal Government. If we experience a loss and IXP is required to pay under its insurance policy, we would ultimately record the loss to the extent of the required payment. Therefore, insurance coverage provided by IXP should not be considered as the equivalent of third-party insurance, but rather as a modified form of self-insurance. In addition, BPLP has issued a guarantee to cover liabilities of IXP in the amount of $20.0 million.

We continue to monitor the state of the insurance market in general, and the scope and costs of coverage for acts of terrorism, earthquakes, pandemics and cybersecurity incidents, in particular, but we cannot anticipate what coverage will be available on commercially reasonable terms in future policy years. There are other types of losses, such as from wars, for which we cannot obtain insurance at all or at a reasonable cost. With respect to such losses and losses from acts of terrorism, earthquakes, pandemics or other catastrophic events, if we experience a loss that

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is uninsured or that exceeds policy limits, we could lose the capital invested in the damaged properties, as well as the anticipated future revenues from those properties. Depending on the specific circumstances of each affected property, it is possible that we could be liable for mortgage indebtedness or other obligations related to the property. Any such loss could materially and adversely affect our business, financial condition and results of operations.

Actual or threatened terrorist attacks or other criminal acts may adversely affect our ability to generate revenues and the value of our properties.

We have significant investments in large metropolitan markets that have been, and may continue to be, the targets of actual or threatened terrorism attacks and other criminal acts, including Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC. As a result, some clients in these markets may (1) choose to relocate their businesses to other markets or to lower-profile office buildings within these markets that may be perceived to be less likely targets of future terrorist activity and/or (2) perceive a need for or request security enhancements . This could result in an overall decrease in the demand for office space in these markets generally or in our properties in particular, which could increase vacancies in our properties, necessitate that we lease our properties on less favorable terms or both, and/or increase our costs related to security, equipment and personnel. In addition, future terrorist attacks in these markets could directly or indirectly damage our properties, both physically and financially, or cause losses that materially exceed our insurance coverage. As a result of the foregoing, our ability to generate revenues and the value of our properties could decline materially. See also “ —Some potential losses are not covered by insurance. ”

We face risks associated with security breaches, incidents and compromises through cyber-attacks, cyber intrusions or otherwise, as well as other significant disruptions of our information technology (IT) networks and related systems.

We face risks associated with security breaches, incidents, and compromises, whether through cyber attacks or cyber intrusions over the internet, malware, computer viruses, attachments to e-mails, persons inside our organization or persons with access to systems inside our organization, social engineering tactics, and other significant disruptions of our IT networks and related systems. The risk of a security breach, incident, compromise, or disruption, particularly through cyber attack or cyber intrusion, including by computer hackers, foreign governments and cyber terrorists, has generally increased as the number, intensity and sophistication of attempted attacks and intrusions from around the world have increased. Our IT networks and related systems are essential to the operation of our business and our ability to perform day-to-day operations (including managing our building systems and accounting for our business operations) and, in some cases, may be critical to the operations of certain of our clients.

Although we make efforts to maintain the security and integrity of our IT networks and related systems, and we have implemented various measures designed to manage the risk of a security breach, incident, compromise or disruption, there can be no assurance that our security efforts and measures will be effective or that attempted security breaches, incident, compromise or disruptions would not be successful or damaging. Even the most well-protected information, networks, systems and facilities remain potentially vulnerable because the techniques used in such attempted security breaches evolve and generally are not recognized until launched against a target, and in some cases, are designed not to be detected and, in fact, may not be detected. Accordingly, we may be unable to anticipate these techniques or to implement adequate security barriers or other preventative measures, and thus it is impossible for us to entirely mitigate this risk.

Like other businesses, we have been, and expect to continue to be, subject to attempts at unauthorized access of our network, mishandling or misuse, computer viruses or malware, cyber attacks and intrusions and other events of varying degrees. To date, these events have not had, individually or in the aggregate, a material adverse effect on our operations or business. However, a security breach, incident, compromise or other significant disruption involving our IT networks and related systems could:

• disrupt the proper functioning of our networks and systems and therefore our operations and/or those of certain of our clients;

• result in misstated financial reports, violations of loan covenants, missed reporting deadlines and/or missed permitting deadlines;

• result in our inability to properly monitor our compliance with the rules and regulations regarding BXP’s qualification as a REIT;

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• result in the unauthorized access to, and destruction, loss, theft, misappropriation or release of, proprietary, confidential, sensitive or otherwise valuable information of ours or others, which others could use to compete against us or which could expose us to damage and claims or threats by third-parties for disruptive, destructive or otherwise harmful purposes and outcomes;

• result in our inability to maintain the building systems relied upon by our clients for the efficient use of their leased space;

• require significant management attention and resources to remedy any damages that result;

• subject us to claims for breach of contract, damages, credits, penalties or termination of leases or other agreements or subject us to litigation and regulatory investigations and related fines and penalties;

• be uninsured or exceed policy limits, increase operating costs, including insurance expenses, or make future cyber risk coverage unavailable on commercially reasonable terms ; and

• damage our reputation among our clients and investors generally.

Any one or more of the foregoing could have a material adverse effect on our results of operations, financial condition and cash flows. Refer to Part I, Item 1C. Cybersecurity in this Form 10-K for more information.

The use of technology based on artificial intelligence and machine learning presents risks and challenges that may adversely affect our business and results of operations.

We use artificial intelligence and machine learning technology (collectively, “AI”) capabilities with the goal of enhancing efficiencies in conducting our business. Our deployment and application of AI remains ongoing. While these AI tools hold promise in optimizing our work processes and driving efficiencies, their use, whether authorized or unauthorized, presents risks, challenges and unintended consequences that could adversely affect our business and results of operations or those of our clients. These include, but are not limited to:

• the release, leak or disclosure of proprietary, confidential, sensitive or otherwise valuable information as a result of or in connection with our use of AI tools;

• the incorporation of AI by our workforce (even when used in accordance with our guidelines) and our clients, vendors, contractors and other third-parties into their products or services, with or without our knowledge, in a manner that could give rise to allegations, legal claims and other issues pertaining to data privacy, information security, proprietary information and intellectual property considerations;

• the production of incomplete, inaccurate or otherwise flawed outputs, some of which may be difficult to detect, and the reliance on such outputs which could result in adverse consequences to us, including exposure to reputational and competitive harm, customer loss, legal liability, errors in our decision-making, process development or other business activities or otherwise have a negative impact on us; and

• the evolving legal regulations relating to AI, which may require significant resources to modify and maintain business practices to comply with applicable law or otherwise result in legal or regulatory action or create additional liabilities, the nature of which cannot be determined at this time.

We have implemented guidelines and policies specifically governing the use of AI tools in the workplace. Although we aim to use AI responsibly and securely and attempt to mitigate ethical and legal issues presented by its use, we may ultimately be unsuccessful in identifying or resolving issues before they arise. There can be no assurance that we will properly implement AI, and the failure to do so could have a material adverse effect on our results of operations or financial condition.

We face risks associated with our clients and contractual counterparties being designated “Prohibited Persons” by the Office of Foreign Assets Control.

Pursuant to Executive Order 13224 and other laws, the Office of Foreign Assets Control of the United States Department of the Treasury (“OFAC”) maintains a list of persons designated as terrorists or who are otherwise blocked or banned (“Prohibited Persons”). OFAC regulations and other laws prohibit conducting business or engaging in transactions with Prohibited Persons (the “OFAC Requirements”). Certain of our loan and other agreements require us to comply with OFAC Requirements. We have established a compliance program whereby

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clients and others with whom we conduct business are checked against the OFAC list of Prohibited Persons prior to entering into any agreement and on a periodic basis thereafter. Our leases and other agreements, in general, require the other party to comply with OFAC Requirements. If a client or other party with whom we contract is placed on the OFAC list we may be required by the OFAC Requirements to terminate the lease or other agreement. Any such termination could result in a loss of revenue or a damage claim by the other party that the termination was wrongful.

The outbreak of highly infectious or contagious diseases could adversely impact or cause disruption to our financial condition, results of operations, cash flows and liquidity and that of our clients.

Public health crises such as pandemics and similar outbreaks could adversely impact our business. The full extent to which any future pandemic or similar outbreak may impact our operations and those of our clients will depend on future developments, which are highly uncertain and cannot be predicted. Factors related to any public health crises that could have a material adverse effect on our results of operations and financial condition include:

• changes made by companies in response to a pandemic that could lead to a sustained shift away from collective in-person work environments or relocations away from the markets in which we operate, either of which could adversely affect the overall demand for workplaces in the regions in which we operate;

• reduced economic activity and/or supply chain disruptions or delays in delivery of products, services or other materials necessary for our clients that impact our clients’ businesses, financial condition or liquidity, may cause, one or more of our clients to be unable to meet their obligations to us, including their ability to make timely rental payments, in full or at all, or to otherwise seek modifications of such obligations, including rent concessions, deferrals or abatements, or to declare bankruptcy. Any one or more of the foregoing could:

• reduce our cash flows,

• adversely impact our ability to finance, refinance or sell a property,

• adversely impact our ability to continue paying distributions to our securityholders at current levels, or at all, and

• result in additional legal and other costs to enforce our rights, collect rent and/or re-lease the space occupied by the distressed client;

• the degree to which our clients’ businesses are negatively impacted could require us to write-off a client’s accrued rent balance and this could have a material adverse effect on our results of operations and liquidity;

• new laws, governmental policies, and similar actions, including legal restrictions on prosecutions, could adversely impact public safety and thereby adversely affect (1) the desirability of clients to lease space in our properties or markets, and (2) businesses’ office re-population plans;

• the impact of a pandemic could result in an event or change in circumstances that results in an impairment in the value of our properties or our investments in unconsolidated joint ventures, and any such impairment could have a material adverse effect on our results of operations in the periods in which the charge is taken;

• we may be unable to restructure or amend leases with certain of our clients on terms favorable to us or at all;

• the impact and validity of interpretations of lease provisions and applicable laws related to claims by clients regarding their obligations to pay rent as a result of a pandemic, and any adverse court rulings or decisions interpreting these provisions and laws, could have a material adverse effect on our results of operations and liquidity;

• the impact of governmental and business travel limitations and restrictions could result in temporary or sustained periods of decreased demand for stays at our hotel property;

• the extent of labor shortages, disruptions in the supply chains, inflation impacting costs of materials, delays in permitting or inspections, and other factors could result in our failure to meet the development milestones set forth in any applicable lease agreement, which could provide the client the right to terminate its lease or entitle the client to monetary damages, delay the commencement or completion of

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construction and our anticipated lease-up plans for a development/redevelopment project or our overall development pipeline, including recognizing revenue for new leases, that may cause returns on investment to be less than projected, and/or increase the costs of construction of new or existing projects, any of which could adversely affect our investment returns, profitability and/or our future growth; and

• the potential that business interruption, loss of rental income and/or other associated expenses related to our operations will not be covered in whole or in part by our insurance policies, which may increase unreimbursed liabilities.

We face risks associated with climate change and severe weather events, as well as the regulatory efforts intended to reduce the effects of climate change.

The physical effects of climate change could have a material adverse effect on our properties, operations and business. For example, many of our properties are located along the East and West coasts, particularly those in the central business districts of Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC. To the extent climate change causes changes in weather patterns, our markets could experience increases in storm intensity, extreme temperatures, rising sea-levels, extreme drought and/or wildfires. Over time, these conditions could result in declining demand for office space in our buildings or increased costs associated with infrastructure-related remediation projects. Climate change may also have indirect effects on our business by making property insurance unavailable or by increasing the cost of (i) property insurance on terms we find acceptable, (ii) real estate taxes or other assessments, (iii) energy and (iv) property maintenance. In addition, we face transition risks related to federal, state and local legislation and regulations that are being implemented, are under consideration to mitigate the effects of climate change or that require increased environmental disclosures and reporting. The costs of complying with evolving regulatory requirements, including GHG emissions regulations and policies, could negatively impact our financial results.

For additional discussion regarding our approach to climate resiliency and our continued commitment to transparent reporting of sustainability performance indicators, see “ Item 1. Business—Business and Growth Strategies—Sustainability ” and our annual Sustainability & Impact Report available on our website at http://www.bxp.com under the heading “Commitment.”

Potential liability for environmental contamination could result in substantial costs.

Under federal, state and local environmental laws, ordinances and regulations, we may be required to investigate and clean up the effects of releases of hazardous or toxic substances or petroleum products at or migrating from our properties simply because of our current or past ownership or operation of the real estate. If unidentified environmental problems arise, we may have to make substantial payments, which could adversely affect our cash flow and our ability to make distributions to our securityholders, because: as owner or operator we may have to pay for property damage and for investigation and clean-up costs incurred in connection with the contamination; the law typically imposes clean-up responsibility and liability regardless of whether the owner or operator knew of or caused the contamination; even if more than one person may be responsible for the contamination, each person who shares legal liability under the environmental laws may be held responsible for all of the clean-up costs; and governmental entities and third parties may sue the owner or operator of a contaminated site for damages and costs.

These costs could be substantial and in extreme cases could exceed the amount of our insurance or the value of the contaminated property. We currently carry environmental insurance in an amount and subject to deductibles that we believe are commercially reasonable. Specifically, we carry a pollution legal liability policy with a $20 million limit per incident and a policy aggregate limit of $40 million. The presence or migration of hazardous or toxic substances or petroleum products or the failure to properly remediate contamination may give rise to third-party claims for bodily injury, property damage and/or response costs and may materially and adversely affect our ability to borrow against, sell or rent an affected property. In addition, applicable environmental laws create liens on contaminated sites in favor of the government for damages and costs it incurs in connection with contamination. Changes in laws, regulations and practices and their implementation increasing the potential liability for environmental conditions existing at our properties, or increasing the restrictions on the handling, storage or discharge of hazardous or toxic substances or petroleum products or other actions may result in significant unanticipated expenditures.

Environmental laws also govern the presence, maintenance and removal of asbestos and other building materials. For example, laws require that owners or operators of buildings containing asbestos:

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• properly manage and maintain the asbestos;

• notify and train those who may come into contact with asbestos; and

• undertake special precautions, including removal or other abatement, if asbestos would be disturbed during renovation or demolition of a building.

Such laws may impose fines and penalties on building owners or operators who fail to comply with these requirements and may allow third parties to seek recovery from owners or operators for personal injury associated with exposure to asbestos fibers.

Some of our properties are located in urban and previously developed areas where fill or current or historic industrial uses of the areas have caused site contamination. It is our policy to retain independent environmental consultants to conduct or update Phase I environmental site assessments and asbestos surveys with respect to our acquisition of properties. These assessments generally include a visual inspection of the properties and the surrounding areas, an examination of current and historical uses of the properties and the surrounding areas and a review of relevant state, federal and historical documents, but do not involve invasive techniques such as soil and ground water sampling. Where appropriate, on a property-by-property basis, our practice is to have these consultants conduct additional testing, including sampling for asbestos, for lead and other contaminants in drinking water and, for soil and/or groundwater contamination where underground storage tanks are or were located or where other past site usage creates a potential environmental problem. Even though these environmental assessments are conducted, there is still the risk that:

• the environmental assessments and updates did not identify or properly address all potential environmental liabilities;

• a prior owner created a material environmental condition that is not known to us or the independent consultants preparing the assessments;

• new environmental liabilities have developed since the environmental assessments were conducted; and

• future uses or conditions such as changes in applicable environmental laws and regulations could result in environmental liability for us.

Inquiries about indoor air quality may necessitate special investigation and, depending on the results, remediation beyond our regular indoor air quality testing and maintenance programs. Indoor air quality issues can stem from inadequate ventilation, chemical contaminants from indoor or outdoor sources, and biological contaminants such as molds, pollen, viruses and bacteria. Indoor exposure to chemical or biological contaminants can be alleged to be connected to allergic reactions or other adverse health effects. If these conditions were to occur at one of our properties, we may be subject to third-party claims for personal injury, or may need to undertake a targeted remediation program, including without limitation, special cleaning measures and steps to increase indoor ventilation rates and eliminate sources of contaminants. Such remediation programs could be costly, necessitate the temporary relocation of some or all of the property’s clients or require rehabilitation of the affected property.

Compliance or failure to comply with the Americans with Disabilities Act or other safety regulations and requirements could result in substantial costs.

The Americans with Disabilities Act generally requires that certain buildings, including office buildings, residential buildings and hotels, be made accessible to disabled persons. Noncompliance could result in the imposition of fines by the federal government or the award of damages to private litigants. If, under the Americans with Disabilities Act, we are required to make substantial alterations and capital expenditures in one or more of our properties, including the removal of access barriers, it could adversely affect our financial condition and results of operations, as well as the amount of cash available for distribution to our securityholders.

Our properties are subject to various federal, state and local regulatory requirements, such as state and local fire and life safety requirements. If we fail to comply with these requirements, we could incur fines or private damage awards. We do not know whether existing requirements will change or whether compliance with future requirements will require significant unanticipated expenditures that will affect our cash flow and results of operations.

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Any future international activities will be subject to special risks and we may not be able to effectively manage our international business.

We have underwritten, and in the future may acquire, properties, portfolios of properties or interests in real estate-related entities on a strategic or selective basis in international markets that are new to us. If we acquire properties or platforms located in these markets, we will face risks associated with a lack of market knowledge and understanding of the local economy, forging new business relationships in the area and unfamiliarity with local laws and government and permitting procedures. In addition, our international operations will be subject to the usual risks of doing business abroad such as possible revisions in tax treaties or other laws and regulations, including those governing the taxation of our international income, restrictions on the transfer of funds and uncertainty over terrorist activities. We cannot predict the likelihood that any of these developments may occur. Further, we may in the future enter into agreements with non-U.S. entities that are governed by the laws of, and are subject to dispute resolution in the courts of, another country or region. We cannot accurately predict whether such a forum would provide us with an effective and efficient means of resolving disputes that may arise.

Investments in international markets may also subject us to risks associated with funding increasing headcount, integrating new offices, and establishing effective controls and procedures to regulate the operations of new offices and to monitor compliance with U.S. laws and regulations such as the Foreign Corrupt Practices Act and similar foreign laws and regulations, such as the U.K. Bribery Act.

We may be subject to risks from potential fluctuations in exchange rates between the U.S. dollar and the currencies of the other countries in which we invest.

If we invest in countries where the U.S. dollar is not the national currency, we will be subject to international currency risks from the potential fluctuations in exchange rates between the U.S. dollar and the currencies of those other countries. A significant depreciation in the value of the currency of one or more countries where we have a significant investment may materially affect our results of operations. We may attempt to mitigate any such effects by borrowing in the currency of the country in which we are investing and, under certain circumstances, by hedging exchange rate fluctuations; however, access to capital may be more restricted, or unavailable on favorable terms or at all, in certain locations. For leases denominated in international currencies, we may use derivative financial instruments to manage the international currency exchange risk. We cannot assure you, however, that our efforts will successfully neutralize all international currency risks.

Risks Related to Our Indebtedness and Financing

Our maturing debt bears interest at lower rates than the current market rates, which has increased, and may continue to increase our interest costs which could adversely impact our ability to refinance existing debt or sell assets on favorable terms or at all.

As of February 20, 2026, we had $2.3 billion outstanding indebtedness, excluding our unconsolidated joint ventures, that bears interest at a variable rate, and we may incur more indebtedness in the future. Approximately $0.9 billion of our variable rate debt has been hedged with interest rates swaps to fix SOFR for all, or a portion of the applicable debt term. As current interest rates remain higher than interest rates on our maturing debt, the interest costs on our debt have increased, which, if current rates are sustained or continue to increase, could adversely affect our cash flow and our ability to pay principal and interest on our debt and our ability to make distributions to our securityholders. Further, elevated interest rates could limit our ability to refinance existing debt when it matures or significantly increase our future interest expense. From time to time, we enter into interest rate swap agreements and other interest rate hedging contracts, including swaps, caps and floors. While these agreements are intended to lessen the impact of rising interest rates on us, they also expose us to the risk that the other parties to the agreements will not perform, we could incur significant costs associated with the settlement of the agreements, the agreements will be unenforceable and the underlying transactions will fail to qualify as highly-effective cash flow hedges under guidance included in ASC 815 “Derivatives and Hedging.” In addition, high interest rates could decrease the amounts third-parties are willing to pay for our assets, thereby limiting our ability to change our portfolio promptly in response to changes in economic or other conditions.

Covenants in our debt agreements could adversely affect our financial condition.

The mortgages on our properties contain customary covenants such as those that limit our ability, without the prior consent of the lender, to further mortgage the applicable property or to modify or discontinue insurance coverage. Our unsecured credit facility, unsecured debt securities and certain secured loans contain customary restrictions, requirements and other limitations on our ability to incur indebtedness, including total debt to asset

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ratios, secured debt to total asset ratios, debt service coverage ratios and minimum ratios of unencumbered assets to unsecured debt, which we must maintain. Our continued ability to borrow under our credit facilities is subject to compliance with our financial and other covenants. In addition, our failure to comply with such covenants could cause a default under the applicable debt agreement, and we may then be required to repay such debt with capital from other sources. Under those circumstances, other sources of capital may not be available to us, or be available only on unattractive terms. Additionally, in the future our ability to satisfy current or prospective lenders’ insurance requirements may be adversely affected if lenders generally insist upon greater insurance coverage against acts of terrorism or losses resulting from earthquakes than is available to us in the marketplace or on commercially reasonable terms.

We rely on debt financing, including borrowings under our unsecured credit facility, issuances of unsecured debt securities and debt secured by individual properties, to finance our existing portfolio, our acquisition and development activities and for working capital. If we are unable to obtain debt financing from these or other sources, or to refinance existing indebtedness upon maturity, our financial condition and results of operations would likely be adversely affected. If we breach covenants in our debt agreements, the lenders can declare a default and, if the debt is secured, can take possession of the property securing the defaulted loan. In addition, our unsecured debt agreements contain specific cross-default provisions with respect to specified other indebtedness, giving the unsecured lenders the right to declare a default if we are in default under other loans in some circumstances. Defaults under our debt agreements could materially and adversely affect our financial condition and results of operations.

We face risks associated with the use of debt to fund acquisitions and developments, including refinancing risk.

We are subject to the risks normally associated with debt financing, including the risk that our cash flow will be insufficient to meet required payments of principal and interest. We anticipate that only a small portion of the principal of our debt will be repaid prior to maturity. Therefore, we are likely to need to refinance at least a portion of our outstanding debt as it matures. There is a risk that we may not be able to refinance existing debt or that the terms of any refinancing will not be as favorable as the terms of our existing debt. If principal payments due at maturity cannot be refinanced, extended or repaid with proceeds from other sources, such as new equity capital, our cash flow may not be sufficient to repay all maturing debt in years when significant “balloon” payments come due. In addition, we may rely on debt to fund a portion of our new investments such as our acquisition and development activity. There is a risk that we may be unable to finance these activities on favorable terms or at all. These conditions, which increase the cost and reduce the availability of debt, may continue or worsen in the future.

We have had and may in the future have agreements with a number of limited partners of BPLP who contributed properties in exchange for partnership interests that require BPLP to maintain for specified periods of time secured debt on certain of our assets and/or allocate partnership debt to such limited partners to enable them to continue to defer recognition of their taxable gain with respect to the contributed property. These tax protection and debt allocation agreements may restrict our ability to repay or refinance debt. As of December 31, 2025, we had one tax protection agreement that could restrict our ability to repay or finance debt.

Our degree of leverage could limit our ability to obtain additional financing or affect the market price of our equity and debt securities.

As of February 20, 2026, our Consolidated Debt was approximately $15.6 billion (excluding unconsolidated joint venture debt).

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The following table presents Consolidated Market Capitalization and the corresponding ratios of Consolidated Debt to Consolidated Market Capitalization (dollars and shares / units in thousands):

February 20, 2026

Shares / Units Outstanding

Common Stock Equivalent

Equivalent Value (1)

Common Stock

Common Operating Partnership Units

Total Equity (A)

Consolidated Debt (B)

Consolidated Market Capitalization (A + B)

Consolidated Debt/Consolidated Market Capitalization [B / (A + B)]

(1) Values are based on the closing price per share of BXP’s Common Stock on February 20, 2026 of $60.88.

(2) Includes LTIP Units (including 2012 OPP Units and earned MYLTIP Units that were granted between 2013 - 2023), but excludes 2025 OPP Units and MYLTIP Units granted between 2024 and 2026 because the performance period for those awards has not yet ended.

Our degree of leverage could affect our ability to obtain additional financing for working capital, capital expenditures, acquisitions, development or other general corporate purposes. Our senior unsecured debt is currently rated investment grade by two major rating agencies. However, there can be no assurance that we will be able to maintain these ratings. In the event our senior debt is downgraded from its current ratings, we would likely incur higher borrowing costs and/or difficulty in obtaining additional financing. Our degree of leverage could also make us more vulnerable to a downturn in business or the economy generally. There is a risk that changes in our debt to market capitalization ratio, which is in part a function of BXP’s stock price, or BPLP’s ratio of indebtedness to other measures of asset value used by financial analysts may have an adverse effect on the market price of our equity or debt securities.

We face risks associated with short-term liquid investments.

We may invest cash balances in a variety of short-term investments that are intended to preserve principal value and maintain a high degree of liquidity while providing current income. From time to time, these investments may include (either directly or indirectly):

• direct obligations issued by the U.S. Treasury;

• obligations issued or guaranteed by the U.S. Government or its agencies;

• taxable municipal securities;

• obligations (including certificates of deposit) of banks and thrifts;

• commercial paper and other instruments consisting of short-term U.S. dollar denominated obligations issued by corporations and banks;

• repurchase agreements collateralized by corporate and asset-backed obligations;

• both registered and unregistered money market funds; and

• other highly rated short-term securities.

Investments in these securities and funds are not insured against loss of principal. Under certain circumstances we may be required to redeem all or part of our investment, and our right to redeem some or all of our investment may be delayed or suspended. In addition, there is no guarantee that our investments in these securities or funds will be redeemable at par value. A decline in the value of our investment or a delay or suspension of our right to redeem may have a material adverse effect on our results of operations or financial condition.

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Risks Related to Our Organization and Structure

Conflicts of interest exist with holders of interests in BPLP.

Sales of properties and repayment of related indebtedness will have different effects on holders of interests in BPLP than on BXP’s stockholders.

Some holders of interests in BPLP could incur adverse tax consequences upon the sale of certain of our properties and on the repayment of related debt which differ from the tax consequences to BXP and its stockholders. Consequently, these holders of partnership interests in BPLP may have different objectives regarding the appropriate pricing and timing of any such sale or repayment of debt. While BXP has exclusive authority under the limited partnership agreement of BPLP to determine when to refinance or repay debt or whether, when, and on what terms to sell a property, subject, in the case of certain properties, to the contractual commitments described below, any such decision would require the approval of BXP’s Board of Directors. While the Board of Directors has a policy with respect to these matters, directors and executive officers could exercise their influence in a manner inconsistent with the interests of some, or a majority, of BXP’s stockholders, including in a manner which could prevent completion of a sale of a property or the repayment of indebtedness.

Agreement not to sell some properties.

We have had and may have in the future agreements with the contributors of properties that we have acquired in exchange for partnership interests in BPLP pursuant to which we have agreed not to sell or otherwise transfer the properties, prior to specified dates, in any transaction that would trigger taxable income to the contributors. In addition, we are responsible for the reimbursement of certain tax-related costs to the prior owners if the subject properties are sold in a taxable sale. In general, our obligations to the prior owners are limited in time and only apply to actual damages suffered.

Also, BPLP has had and may have in the future agreements providing prior owners of properties with the right to guarantee specific amounts of indebtedness and, in the event that the specific indebtedness they guarantee is repaid or reduced, additional and/or substitute indebtedness. These agreements may hinder actions that BPLP may otherwise desire to take to repay or refinance guaranteed indebtedness because doing so would require BPLP to make payments to the prior owners if BPLP violates these agreements.

Limits on changes in control may discourage takeover attempts beneficial to stockholders.

Provisions in BXP’s charter and bylaws and the limited partnership agreement of BPLP, as well as provisions of the Code and Delaware corporate law, may:

• delay or prevent a change of control over BXP or a tender offer, even if such action might be beneficial to BXP’s stockholders; and

• limit BXP’s stockholders’ opportunity to receive a potential premium for their shares of common stock over then-prevailing market prices.

Stock Ownership Limit

To facilitate maintenance of BXP’s qualification as a REIT and to otherwise address concerns relating to concentration of stock ownership, BXP’s charter generally prohibits the ownership, directly, indirectly or beneficially, by any single stockholder of more than 6.6% of the number of outstanding shares of any class or series of its common stock. We refer to this limitation as the “ownership limit.” BXP’s Board of Directors may, in its sole discretion, waive or modify the ownership limit with respect to one or more persons if it is satisfied that ownership in excess of this limit will not jeopardize BXP’s status as a REIT for federal income tax purposes. In addition, under BXP’s charter, each of Mortimer B. Zuckerman and the respective families and affiliates of Mortimer B. Zuckerman and Edward H. Linde, as well as, in general, pension plans and mutual funds, may actually and beneficially own up to 15% of the number of outstanding shares of any class or series of BXP’s equity common stock. Shares owned in violation of the ownership limit will be subject to the loss of rights to distributions and voting and other penalties. The ownership limit may have the effect of inhibiting or impeding a change in control.

BPLP’s Partnership Agreement

BXP has agreed in the limited partnership agreement of BPLP not to engage in specified extraordinary transactions, including, among others, business combinations, unless limited partners of BPLP other than BXP receive, or have the opportunity to receive, either (1) the same consideration for their partnership interests as

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holders of BXP common stock in the transaction or (2) limited partnership units that, among other things, would entitle the holders, upon redemption of these units, to receive shares of common equity of a publicly traded company or the same consideration as holders of BXP common stock received in the transaction. If these limited partners would not receive such consideration, then we cannot engage in the transaction unless limited partners holding at least 75% of the common units of limited partnership interest, other than those held by BXP or its affiliates, consent to the transaction. In addition, BXP has agreed in the limited partnership agreement of BPLP that it will not complete specified extraordinary transactions, including among others, business combinations, in which BXP receives the approval of its common stockholders unless (1) limited partners holding at least 75% of the common units of limited partnership interest, other than those held by BXP or its affiliates, consent to the transaction or (2) the limited partners of BPLP are also allowed to vote and the transaction would have been approved had these limited partners been able to vote as common stockholders on the transaction. Therefore, if BXP’s common stockholders approve a specified extraordinary transaction, the partnership agreement requires the following before it can complete the transaction:

• holders of partnership interests in BPLP, including BXP, must vote on the matter;

• BXP must vote its partnership interests in the same proportion as its stockholders voted on the transaction; and

• the result of the vote of holders of partnership interests in BPLP must be such that had such vote been a vote of stockholders, the business combination would have been approved.

With respect to specified extraordinary transactions, BXP has agreed in BPLP’s partnership agreement to use its commercially reasonable efforts to structure such a transaction to avoid causing its limited partners to recognize gain for federal income tax purposes by virtue of the occurrence of or their participation in such a transaction.

As a result of these provisions, a potential acquirer may be deterred from making an acquisition proposal, and BXP may be prohibited by contract from engaging in a proposed extraordinary transaction, including a proposed business combination, even though BXP stockholders approve of the transaction.

We may change our policies without obtaining the approval of our stockholders.

Our operating and financial policies, including our policies with respect to acquisitions and dispositions of real estate, growth, operations, indebtedness, capitalization and dividends, are exclusively determined by BXP’s Board of Directors. Accordingly, our securityholders do not control these policies.

Risks Related to BXP’s Status as a REIT

Failure to qualify as a REIT would cause BXP to be taxed as a corporation, which would substantially reduce funds available for payment of dividends.

If BXP fails to qualify as a REIT for federal income tax purposes, it will be taxed as a corporation unless certain relief provisions apply. We believe that BXP is organized and qualified as a REIT and intends to operate in a manner that will allow BXP to continue to qualify as a REIT. However, we cannot assure you that BXP is qualified as such, or that it will remain qualified as such in the future. This is because qualification as a REIT involves the application of highly technical and complex provisions of the Code as to which there are only limited judicial and administrative interpretations and involves the determination of facts and circumstances not entirely within our control. Future legislation, new regulations, administrative interpretations or court decisions may significantly change the tax laws or the application of the tax laws with respect to qualification as a REIT for federal income tax purposes or the federal income tax consequences of such qualification.

In addition, we currently hold certain of our properties through subsidiaries that have elected to be taxed as REITs and we may in the future determine that it is in our best interests to hold one or more of our other properties through one or more subsidiaries that elect to be taxed as REITs. If any of these subsidiaries fails to qualify as a REIT for federal income tax purposes, then BXP may also fail to qualify as a REIT for federal income tax purposes.

If BXP or any of its subsidiaries that are REITs fails to qualify as a REIT then, unless certain relief provisions apply, it will face serious tax consequences that will substantially reduce the funds available for payment of dividends for each of the years involved because:

• BXP would not be allowed a deduction for dividends paid to stockholders in computing its taxable income and would be subject to federal income tax at regular corporate rates;

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• BXP also could be subject to the federal alternative minimum tax for tax years ending before January 1, 2018 and possibly increased state and local taxes; and

• unless BXP is entitled to relief under statutory provisions, BXP could not elect to be subject to tax as a REIT for four taxable years following the year during which it was disqualified.

In addition, if BXP fails to qualify as a REIT and the relief provisions do not apply, it will no longer be required to pay dividends. As a result of all these factors, BXP’s failure to qualify as a REIT could impair our ability to raise capital and expand our business, and it would adversely affect the value of BXP’s common stock. If BXP or any of its subsidiaries that are REITs fails to qualify as a REIT but is eligible for certain relief provisions, then it may retain its status as a REIT, but may be required to pay a penalty tax, which could be substantial.

In order to maintain BXP’s REIT status, we may be forced to borrow funds during unfavorable market conditions.

In order to maintain BXP’s REIT status, we may need to borrow funds on a short-term basis to meet the REIT distribution requirements, even if the then-prevailing market conditions are not favorable for these borrowings. To qualify as a REIT, BXP generally must distribute to its stockholders at least 90% of its taxable income each year, excluding capital gains and with certain other adjustments. In addition, BXP will be subject to a 4% nondeductible excise tax on the amount, if any, by which dividends paid in any calendar year are less than the sum of 85% of ordinary income, 95% of capital gain net income and 100% of undistributed income from prior years. We may need short-term debt or long-term debt or proceeds from asset sales, creation of joint ventures or sales of common stock to fund required distributions as a result of differences in timing between the actual receipt of income and the recognition of income for federal income tax purposes, or the effect of non-deductible capital expenditures, the creation of reserves or required debt or amortization payments. Any inability of our cash flows to cover our distribution requirements could have an adverse impact on our ability to raise short- and long-term debt or sell equity securities in order to fund distributions required to maintain BXP’s REIT status.

We may be subject to adverse legislative or regulatory tax changes that could negatively impact our financial condition.

At any time, the U.S. federal income tax laws governing REITs or the administrative interpretations of those laws may be amended, including with respect to our hotel ownership structure. We cannot predict if or when any new U.S. federal income tax law, regulation, or administrative interpretation, or any amendment to any existing U.S. federal income tax law, Treasury regulation or administrative interpretation, will be adopted, promulgated or become effective and any such law, regulation, or interpretation may take effect retroactively. BXP, its taxable REIT subsidiaries, and our securityholders could be adversely affected by any such change in, or any new, U.S. federal income tax law, Treasury regulation or administrative interpretation.

We face possible adverse state and local tax audits and changes in state and local tax laws.

Because BXP is organized and qualifies as a REIT, it is generally not subject to federal income taxes, but we are subject to certain state and local taxes. In the normal course of business, certain entities through which we own real estate either have undergone, or are currently undergoing, tax audits. Although we believe that we have substantial arguments in favor of our positions in the ongoing audits, in some instances there is no controlling precedent or interpretive guidance on the specific point at issue. Collectively, tax deficiency notices received to date from the jurisdictions conducting the ongoing audits have not been material. However, there can be no assurance that future audits will not occur with increased frequency or that the ultimate result of such audits will not have a material adverse effect on our results of operations.

From time to time changes in state and local tax laws or regulations are enacted, which may result in an increase in our tax liability. A shortfall in tax revenues for states and municipalities in which we operate may lead to an increase in the frequency and size of such changes. If such changes occur, we may be required to pay additional taxes on our assets or income. These increased tax costs could adversely affect our financial condition and results of operations and the amount of cash available for the payment of dividends and distributions to our securityholders.

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General Risk Factors

Changes in market conditions could adversely affect the market price of BXP’s common stock.

As with other publicly traded equity securities, the value of BXP’s common stock depends on various market conditions that may change from time to time. Among the market conditions that may affect the value of BXP’s common stock are the following:

• the extent of investor interest in our securities;

• the general reputation of REITs and the sentiment towards the office sector and the attractiveness of our equity securities in comparison to other equity securities, including securities issued by other real estate-based companies;

• our underlying asset value;

• investor confidence in the stock and bond markets, generally;

• national economic conditions;

• changes in tax laws;

• our financial performance;

• changes in our credit ratings;

• differences between the yields paid on other investments available in the market and BXP’s dividend yield; and

• general stock and bond market conditions, including changes in interest rates.

The market value of BXP’s common stock is based primarily upon the market’s perception of our growth potential and our current and potential future earnings and cash dividends. Consequently, BXP’s common stock may trade at prices that are greater or less than BXP’s net asset value per share of common stock. If our future earnings or cash dividends are less than expected, it is likely that the market price of BXP’s common stock will diminish.

Further issuances of equity securities may be dilutive to current securityholders.

The interests of our existing securityholders could be diluted if additional equity securities are issued to finance future developments, acquisitions or repay indebtedness. Our ability to execute our business strategy depends on our access to an appropriate blend of debt financing, including unsecured lines of credit and other forms of secured and unsecured debt, and equity financing, including common and preferred equity.

The number of shares available for future sale could adversely affect the market price of BXP’s stock.

In connection with and subsequent to BXP’s initial public offering, we have completed private placement transactions in which shares of stock of BXP or partnership interests in BPLP were issued to owners of properties we acquired or to institutional investors. This common stock, or common stock issuable in exchange for such partnership interests in BPLP, may be sold in the public securities markets over time under registration rights we granted to these investors. Additional common stock issuable under our employee benefit and other incentive plans, including as a result of the grant of stock options and restricted equity securities, may also be sold in the market at some time in the future. Future sales of BXP common stock in the market could adversely affect the price of its common stock. We cannot predict the effect the perception in the market that such sales may occur will have on the market price of BXP’s common stock.

Our involvement in legal proceedings and other claims may result in substantial monetary and other costs that have a material adverse effect on our results of operations.

From time to time, we are involved in legal proceedings and other claims. We may also be named as defendants in lawsuits allegedly arising out of our actions or the actions of our vendors, contractors, clients or other contractual parties in which such parties have agreed to indemnify, defend and hold us harmless from and against various claims, litigation and liabilities arising in connection with their respective businesses and/or added as an additional insured under certain insurance policies. An unfavorable resolution of any legal proceeding or other claim could have a material adverse effect on our financial condition or results from operations. Regardless of their outcome, legal proceedings and other claims may result in substantial costs and expenses and significantly divert

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the attention of our management. With respect to any legal proceeding or other claim, there can be no assurance that we will be able to prevail, or achieve a favorable settlement or outcome, or that our insurance or the insurance and/or any contractual indemnities of our vendors, contractors, clients or other contractual parties will be sufficient to cover all of our defense costs or any resulting liabilities.

Changes in accounting pronouncements could adversely affect our operating results, in addition to the reported financial performance of our clients.

Accounting policies and methods are fundamental to how we record and report our financial condition and results of operations. Uncertainties posed by various initiatives of accounting standard-setting by the Financial Accounting Standards Board and the Securities and Exchange Commission, which create and interpret applicable accounting standards for U.S. companies, may change the financial accounting and reporting standards or their interpretation and application of these standards that govern the preparation of our financial statements. Changes include, but are not limited to, changes in revenue recognition, lease accounting and the adoption of accounting standards likely to require the increased use of “fair-value” measures.

These changes could have a material impact on our reported financial condition and results of operations. In some cases, we could be required to apply a new or revised standard retroactively, resulting in potentially material restatements of prior period financial statements. Similarly, these changes could have a material impact on our clients’ reported financial condition or results of operations or could affect our clients’ preferences regarding leasing real estate.

Item 1B. Unresolved Staff Comments.

None.

Item 1C. Cybersecurity.

Our information technology (“IT”) networks and related systems are essential to the efficient operation of our business and our ability to perform day-to-day operations (including managing our building systems and accounting for our business operations). In some cases, our clients’ operations depend on our building systems. The risk of a security breach, incident, compromise or disruption, particularly through cyber-attack or cyber intrusion, including by computer hackers, foreign governments and cyber terrorists, has generally increased as the number, intensity and sophistication of attempted attacks and intrusions from around the world have increased. Like other businesses, we have been, and expect to continue to be, subject to attempts at unauthorized access of our network, mishandling or misuse, computer viruses or malware, cyber-attacks and intrusions and other events of varying degrees. To date, these events have not, individually or in the aggregate, had a material adverse effect on our operations or business. In addition, we are not aware of any risks from cybersecurity threats, including as a result of any cybersecurity incidents, that have materially affected or are reasonably likely to materially affect our Company, including our business strategy, results of operations, or financial condition. See Item 1A. “Risk Factors” for additional discussion of the cybersecurity risks related to our Company.

Cybersecurity Risk Management & Strategy

We have implemented and maintain a cybersecurity program that is designed to identify, assess and manage risks from cybersecurity threats and was established by reference to the National Institute of Standards and Technology (“NIST”) Cybersecurity Framework. The primary goal of our cybersecurity program is to prevent cybersecurity incidents to the extent feasible, while simultaneously increasing our system resilience in an effort to minimize the business impact should an incident occur. We aim to take an active approach to monitoring and evaluating our cybersecurity threat environment and risk profile as part of our cybersecurity program, which is administered by our information systems (“IS”) department and led by our Senior Vice President, Chief Information Officer (“CIO”). Our CIO is primarily responsible for the direction and implementation of technology, applications and security at BXP and has 30 years of technology experience developed across multiple industries, including commercial real estate, in guiding organizations through strategic initiatives that span technology, cybersecurity, and digital transformations.

We maintain written information security policies and procedures, including a Cybersecurity Incident Response Plan (“CIRP”) for incidents involving potential or actual compromises of information security. Our CIRP is overseen by the cyber executive response team, which is chaired by our Vice President, Risk Management and includes representatives from our IS and legal departments. In the event of a cybersecurity incident, we have established

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procedures to (i) mobilize third-party subject matter experts and (ii) notify executive leadership and the Audit Committee and/or the full Board of Directors, in each case, as appropriate.

As part of our overall cybersecurity program, we also conduct:

• Regular assessments of our cybersecurity program . We assess our cybersecurity program against the NIST Cybersecurity Framework through annual internal assessments, and, every two years, we engage a third-party consultant to conduct an additive cyber assessment. These assessments review, among other things, our IT security measures and activities for alignment with the NIST Cybersecurity Framework.

• Periodic penetration testing & vulnerability assessments . On an annual basis, we engage a third-party consultant to conduct two penetration tests per year. We also conduct vulnerability assessments on a monthly basis.

• Regular cybersecurity awareness trainings & simulations . We conduct cybersecurity awareness training for employees and primary on-site providers during onboarding and at least annually thereafter. In addition to annual trainings, we conduct regular phishing simulations in an effort to raise awareness of spoofed or manipulated electronic communications and other security threats, as well as annual tabletop simulations.

In addition, our internal audit function integrates the assessment and identification of cybersecurity-related risks into our annual overall enterprise risk assessment (“ERA”). The ERA process is designed to assess and identify the key risks that management believes could adversely impact our business operations or impede the achievement of our business objectives, which includes an assessment of our cybersecurity program and the cybersecurity-related risks that we face. To the extent the ERA identifies a heightened cybersecurity-related risk(s), we have implemented a process for the risk(s) to be presented to the Audit Committee and the full Board of Directors, as appropriate.

We utilize certain third-party service providers to perform select functions. These third-party service providers also face cybersecurity threats, and a cybersecurity incident impacting any of our third-party service providers could also indirectly affect our operations, performance and results of operations. To date, none of our third-party service providers’ cybersecurity incidents have been, individually or in the aggregate, material to us. We have a data security committee, consisting of members from various BXP departments, including IS, legal and risk management, that meets periodically to assess, identify and manage cybersecurity risks related to certain third-party service providers and to protect our critical financial and sensitive business information, as well as personally identifiable information (collectively, “Sensitive Information”). The data security committee has implemented processes for evaluating the risk profile of those service providers that handle or have access to Sensitive Information, which informs applicable contractual obligations with these service providers. This evaluation, which occurs prior to onboarding, is designed to consider the nature of the services to be provided, the level of sensitivity and quantity of the information that the service provider handles or has access to, and the identity of the service provider.

Cybersecurity Governance

Our Board of Directors is primarily responsible for risk oversight and discharges its responsibility directly and indirectly through its committees. In general, our risk management is designed to be facilitated through a top-down and bottom-up communication structure whereby the Board and/or its committees provide oversight and direction, and management is charged with the day-to-day management of risks, regular assessment of the risk environment and regular reporting to the Board, which may include management reports and reports from outside advisors and consultants engaged by the Board, a specific committee or management, as appropriate. This overall risk management and oversight framework includes risks related to cybersecurity threats.

Pursuant to its charter, the Audit Committee oversees management’s risk management processes related to assessing, identifying and managing cybersecurity risks in an effort to, among other things, help align our risk exposure with our strategic objectives. Our CIO meets with our Audit Committee at least two times each year to discuss, among other things, recent trends in cyber risks, cybersecurity incidents, if any, and our cybersecurity defense strategy to protect against cyber-attacks and intrusions. These discussions with the Audit Committee are led by our CIO and senior management. The Audit Committee provides regular updates to the full Board of Directors on matters under its purview, including risk management and cybersecurity matters.

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Item 2. Properties.

At December 31, 2025, we owned or had joint venture interests in 179 commercial real estate properties, aggregating approximately 52.6 million net rentable square feet of primarily premier workplaces, including eight properties under construction/redevelopment totaling approximately 3.5 million net rentable square feet. Our properties consisted of (1) 157 office and life sciences properties (including four properties under construction/redevelopment), (2) 14 retail properties (including one property under construction), (3) seven residential properties (including three properties under construction) and (4) one hotel. The table set forth below shows information relating to the properties we owned, or in which we had an ownership interest, at December 31, 2025, and it includes properties held by both consolidated and unconsolidated joint ventures.

Properties

Location

% Occupied as of December 31, 2025 (1)

Number of Buildings

Net Rentable Square Feet

Office

767 Fifth Avenue (The GM Building) (60% ownership)

New York, NY

200 Clarendon Street

Boston, MA

601 Lexington Avenue (55% ownership)

New York, NY

399 Park Avenue

New York, NY

Salesforce Tower

San Francisco, CA

800 Boylston Street - The Prudential Center

Boston, MA

7 Times Square (55% ownership)

New York, NY

100 Federal Street (55% ownership)

Boston, MA

Colorado Center (50% ownership) (2)

Santa Monica, CA

Santa Monica Business Park

Santa Monica, CA

599 Lexington Avenue

New York, NY

Reston Next

Reston, VA

250 West 55th Street

New York, NY

Embarcadero Center Four

San Francisco, CA

111 Huntington Avenue - The Prudential Center

Boston, MA

200 Fifth Avenue (26.69% ownership) (2)

New York, NY

Embarcadero Center One

San Francisco, CA

Embarcadero Center Two

San Francisco, CA

Atlantic Wharf Office (55% ownership)

Boston, MA

Gateway Commons (50% Ownership) (2) (3)

South San Francisco, CA

Embarcadero Center Three

San Francisco, CA

Safeco Plaza (33.67% ownership) (2)

Seattle, WA

Madison Centre

Seattle, WA

7750 Wisconsin Avenue (50% ownership) (2)

Bethesda, MD

Dock 72 (50% ownership) (2)

Brooklyn, NY

100 Causeway Street (50% ownership) (2)

Boston, MA

South of Market

Reston, VA

Mountain View Research Park (4)

Mountain View, CA

Fountain Square

Reston, VA

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Properties

Location

% Occupied as of December 31, 2025 (1)

Number of Buildings

Net Rentable Square Feet

901 New York Avenue

Washington, DC

680 Folsom Street

San Francisco, CA

101 Huntington Avenue - The Prudential Center

Boston, MA

145 Broadway

Cambridge, MA

2100 Pennsylvania Avenue

Washington, DC

2200 Pennsylvania Avenue

Washington, DC

360 Park Avenue South (71.11% ownership) (2)

New York, NY

Bay Colony Corporate Center

Waltham, MA

One Freedom Square

Reston, VA

Two Freedom Square

Reston, VA

325 Main Street

Cambridge, MA

The Hub on Causeway - Podium (50% ownership) (2)

Boston, MA

888 Boylston Street - The Prudential Center

Boston, MA

One and Two Discovery Square

Reston, VA

Weston Corporate Center

Weston, MA

510 Madison Avenue

New York, NY

One Reston Overlook

Reston, VA

535 Mission Street

San Francisco, CA

Waltham Weston Corporate Center

Waltham, MA

230 CityPoint

Waltham, MA

Wisconsin Place Office

Chevy Chase, MD

17Fifty Presidents Street

Reston, VA

Democracy Tower

Reston, VA

355 Main Street

Cambridge, MA

1330 Connecticut Avenue

Washington, DC

10 CityPoint

Waltham, MA

510 Carnegie Center

Princeton, NJ

500 North Capitol Street, N.W. (30% ownership) (2)

Washington, DC

90 Broadway

Cambridge, MA

255 Main Street

Cambridge, MA

20 CityPoint

Waltham, MA

77 CityPoint

Waltham, MA

Sumner Square

Washington, DC

University Place

Cambridge, MA

North First Business Park (5)

San Jose, CA

890 Winter Street

Waltham, MA

150 Broadway

Cambridge, MA

Capital Gallery

Washington, DC

Reservoir Place (6)

Waltham, MA

206 Carnegie Center

Princeton, NJ

210 Carnegie Center

Princeton, NJ

Kingstowne Two

Alexandria, VA

105 Broadway

Cambridge, MA

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Properties

Location

% Occupied as of December 31, 2025 (1)

Number of Buildings

Net Rentable Square Feet

212 Carnegie Center

Princeton, NJ

214 Carnegie Center

Princeton, NJ

2440 West El Camino Real

Mountain View, CA

506 Carnegie Center

Princeton, NJ

Two Reston Overlook

Reston, VA

508 Carnegie Center

Princeton, NJ

202 Carnegie Center

Princeton, NJ

804 Carnegie Center

Princeton, NJ

101 Carnegie Center

Princeton, NJ

504 Carnegie Center

Princeton, NJ

502 Carnegie Center

Princeton, NJ

1265 Main Street (50% ownership) (2)

Waltham, MA

701 Carnegie Center

Princeton, NJ

153 Second Avenue

Waltham, MA

104 Carnegie Center

Princeton, NJ

103 Carnegie Center

Princeton, NJ

Reston Next Office Phase II

Reston, VA

Reservoir Place North

Waltham, MA

32 Hartwell Avenue

Lexington, MA

302 Carnegie Center

Princeton, NJ

211 Carnegie Center

Princeton, NJ

92 Hayden Avenue

Lexington, MA

690 Folsom Street

San Francisco, CA

201 Carnegie Center

Princeton, NJ

Subtotal for Office Properties

Life Sciences

180 CityPoint

Waltham, MA

200 West Street

Waltham, MA

125 Broadway

Cambridge, MA

880 Winter Street

Waltham, MA

300 Binney Street (55% ownership)

Cambridge, MA

103 CityPoint

Waltham, MA

33 Hayden Avenue

Lexington, MA

250 Binney Street

Cambridge, MA

100 Hayden Avenue

Lexington, MA

211 Second Avenue

Waltham, MA

Subtotal for Life Sciences Properties

Retail

The Prudential Center (retail shops)

Boston, MA

Fountain Square Retail

Reston, VA

Kingstowne Retail

Alexandria, VA

Santa Monica Business Park Retail

Santa Monica, CA

Star Market at the Prudential Center

Boston, MA

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Properties

Location

% Occupied as of December 31, 2025 (1)

Number of Buildings

Net Rentable Square Feet

Avant Retail

Reston, VA

The Point

Waltham, MA

Subtotal for Retail Properties

Residential

Skymark - Reston Next Residential

(508 units) (20% ownership) (2)

Reston, VA

The Skylyne (402 units)

Oakland, CA

Hub50House (440 units) (50% ownership) (2)

Boston, MA

The Lofts at Atlantic Wharf (86 units) (5)

Boston, MA

Subtotal for Residential Properties

Hotel

Boston Marriott Cambridge (437 rooms)

Cambridge, MA

Subtotal for Hotel Property

Subtotal for In-Service Properties

Properties Under Construction/Redevelopment (11)

Office

725 12th Street (redevelopment)

Washington, DC

343 Madison Avenue

New York, NY

Laboratory/Life Sciences

290 Binney Street (55% ownership)

Cambridge, MA

651 Gateway (redevelopment) (50% ownership) (2) (12)

South San Francisco, CA

Residential

121 Broadway Street (439 units)

Cambridge, MA

17 Hartwell Avenue (312 Units) (20% ownership) (2)

Lexington, MA

290 Coles Street (670 Units) (19.46% ownership) (2)

Jersey City, NJ

Retail

Reston Next Retail (13)

Reston, VA

Subtotal for Properties Under Construction/Redevelopment

Total Portfolio

(1) Represents signed leases for in-service properties for which revenue recognition has commenced in accordance with accounting principles generally accepted in the United States (“GAAP”).

(2) Property is an unconsolidated joint venture.

(3) Includes 681 Gateway, which is a laboratory/life sciences property. On January 2, 2026, we sold our interest in the joint venture that owns Gateway Commons (See Note 17 to the Consolidated Financial Statements).

(4) Includes 453 Ravendale Drive.

(5) The property was sold subsequent to December 31, 2025 (See Note 17 to the Consolidated Financial Statements).

(6) During the first quarter of 2025, approximately 361,000 net rentable square feet was taken out of service to be held for future redevelopment.

(7) Percentage occupied is not included in the calculation of the Total Portfolio occupancy rate for In-Service Properties as of December 31, 2025.

(8) Includes 22,442 square feet of retail space that is approximately 42.9% occupied as of December 31, 2025. This amount is not included in the calculation of the Total Portfolio occupancy rate for In-Service Properties as of December 31, 2025.

(9) Represents the weighted-average room occupancy for the year ended December 31, 2025. This amount is not included in the calculation of the Total Portfolio occupancy rate for In-Service Properties as of December 31, 2025.

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(10) Includes 4,260 square feet of retail space that is 100% occupied as of December 31, 2025. This amount is not included in the calculation of the Total Portfolio occupancy rate for In-Service Properties as of December 31, 2025.

(11) Represents percentage leased as of February 20, 2026, including leases with future commencement dates. Percentage leased excludes 651 Gateway which was sold on January 2, 2026.

(12) The property was 27% placed in-service as of December 31, 2025. On January 2, 2026, we sold our interest in the joint venture that owns 651 Gateway (See Note 17 to the Consolidated Financial Statements).

(13) The property was fully placed in-service on January 16, 2026.

(14) Total percentage occupied excludes Residential and 651 Gateway which was sold on January 2, 2026.

Percentage Occupied and Average Annualized Revenue per Square Foot for In-Service Properties

The following table sets forth our percentage occupied and average annualized revenue per square foot on a historical basis for our In-Service Properties.

December 31,

Percentage occupied (1)

Average annualized revenue per square foot (2)

(1) Represents the quotient obtained by dividing (A) the aggregate number of square feet subject to signed leases, excluding hotel and residential properties, for which revenue recognition has commenced in accordance with GAAP by (B) the total number of square feet in our in-service portfolio.

(2) Represents the monthly contractual base rents and recoveries from clients under existing leases as of December 31, of each year presented, multiplied by twelve. These annualized amounts are before rent abatements and include expense reimbursements, which may be estimates as of such date. The aggregate amounts of rent abatements per square foot under existing leases as of December 31, 2025, 2024, 2023, 2022 and 2021 for the succeeding twelve-month period were $3.19, $2.14, $2.47, $1.56, and $2.15, respectively.

Top 20 Clients by Square Feet

Our 20 largest clients by square feet as of December 31, 2025 were as follows:

Client

Square Feet (1)

% of In-Service Portfolio (1)

Salesforce

Google

Fannie Mae

Akamai Technologies

Snap

Microsoft

Ropes & Gray

Kirkland & Ellis

Biogen

Integrated Holding Group

Bain Capital

Marriott

Allen Overy Shearman Sterling

Leidos

Blue Cross Blue Shield

Arnold & Porter Kaye Scholer

Bechtel Corporation

WeWork

Mass Financial Services

Bank of America

(1) Amounts are calculated based on our consolidated portfolio square feet, plus our share of the square feet from the unconsolidated joint ventures properties (calculated based on our ownership percentage), minus our partners’ share of

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square feet from our consolidated joint venture properties (calculated based upon the partners’ percentage ownership interests).

Client Industry Diversification

Our client industry diversification by square feet as of December 31, 2025 was as follows:

Sector

% of In-Service Portfolio (1)

Technology & Media

Legal Services

Financial Services - all other

Life Sciences

Real Estate & Insurance

Other Professional Services

Retail

Financial Services - commercial & investment banking

Manufacturing

Government / Public Administration

Other

(1) Amounts are calculated based on our consolidated portfolio square feet, plus our share of the square feet from the unconsolidated joint ventures properties (calculated based on our ownership percentage), minus our partners’ share of square feet from our consolidated joint venture properties (calculated based upon the partners’ percentage ownership interests).

Lease Expirations (1)(2)(3)

Year of Lease Expiration

Rentable Square Feet Subject to Expiring Leases

Current Annualized Contractual Rent Under Expiring Leases Without Future Step-Ups (4)

Current Annualized Contractual Rent Under Expiring Leases Without Future Step-Ups p.s.f. (4)

Current Annualized Contractual Rent Under Expiring Leases With Future Step-Ups (5)

Current Annualized Contractual Rent Under Expiring Leases With Future Step-Ups p.s.f. (5)

Percentage of Total Square Feet

Thereafter

(1) Includes 100% of unconsolidated joint venture properties. Does not include residential units or the hotel.

(2) Does not include data for leases expiring in a particular year when leases for the same space have already been signed with replacement clients with future commencement dates. In those cases, the data is included in the year in which the future lease with the replacement client expires.

(3) Lease expirations exclude Gateway Commons and North First Business Park. We sold our interest in the joint venture that owns Gateway Commons on January 2, 2026. North First Business Park was sold on January 14, 2026. See Note 17 to the Consolidated Financial Statements.

(4) Represents the monthly contractual base rent and recoveries from clients under existing leases as of December 31, 2025 multiplied by twelve. This amount reflects total rent before any rent abatements and includes expense reimbursements, which may be estimates as of such date.

(5) Represents the monthly contractual base rent under expiring leases with future contractual increases upon expiration and recoveries from clients under existing leases as of December 31, 2025 multiplied by twelve. This amount reflects total rent before any rent abatements and includes expense reimbursements, which may be estimates as of such date.

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Item 3. Legal Proceedings.

We are subject to various legal proceedings and claims that arise in the ordinary course of business. Many of these matters are covered by insurance. Management believes that the final outcome of such matters will not have a material adverse effect on our financial position, results of operations or liquidity.

Item 4. Mine Safety Disclosures.

Not Applicable.

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PART II

Item 5. Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities.

The common stock of BXP, Inc. is listed on the New York Stock Exchange under the symbol “BXP.” At February 20, 2026, BXP had approximately 943 stockholders of record.

There is no established public trading market for BPLP’s common units. On February 20, 2026, there were approximately 283 holders of record and 177,458,651 common units outstanding, 158,629,124 of which were held by BXP.

To maintain its qualification as a REIT, BXP must make annual distributions to its stockholders of at least 90% of its taxable income (not including net capital gains and with certain other adjustments). BXP has adopted a policy of paying regular quarterly dividends on its common stock, and, as BPLP’s general partner, BXP has adopted a policy of paying regular quarterly distributions on common units of BPLP.

Cash distributions have been paid on the common stock of BXP and BPLP’s common units since BXP’s initial public offering in 1997. Distributions are declared at the discretion of the Board of Directors of BXP and depend on actual and anticipated cash from operations, our financial condition, capital requirements, the annual distribution requirements under the REIT provisions of the Code and other factors the Board of Directors of BXP may consider relevant.

Stock Performance Graph

The following graph provides a comparison of cumulative total stockholder return for the period from December 31, 2020 through December 31, 2025, among BXP, Standard & Poor’s (“S&P”) 500 Index, FTSE Nareit Equity REIT Total Return Index (the “Equity REIT Index”) and the FTSE Nareit Office REIT Index (the “Office REIT Index”). The Equity REIT Index includes all tax-qualified equity REITs listed on the New York Stock Exchange, the American Stock Exchange and the Nasdaq Stock Market. Equity REITs are defined as those with 75% or more of their gross invested book value of assets invested directly or indirectly in the equity ownership of real estate. The Office REIT Index includes all office REITs included in the Equity REIT Index. Data for BXP, the S&P 500 Index, the Equity REIT Index and the Office REIT Index was provided to us by Nareit. Upon written request, we will provide any stockholder with a list of the REITs included in the Equity REIT Index and the Office REIT Index. The stock performance graph assumes an investment of $100 in each of BXP and the three indices, and the reinvestment of any dividends. The historical information set forth below is not necessarily indicative of future performance. The data shown is based on the share prices or index values, as applicable, at the end of each month shown.

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As of the year ended December 31,

BXP, Inc.

S&P 500 Index

Equity REIT Index

Office REIT Index

BXP

(a) During the three months ended December 31, 2025, BXP issued an aggregate of 147,217 shares of common stock in exchange for 147,217 common units of limited partnership held by certain limited partners of BPLP. Of these shares, 67,569 shares were issued in reliance on an exemption from registration under Section 4(a)(2) of the Securities Act of 1933, as amended. BXP relied on the exemption under Section 4(a)(2) based upon factual representations received from the limited partner who received the shares of common stock.

(b) Not Applicable.

(c) Issuer Purchases of Equity Securities.

Period

Total Number of Shares of Common Stock

Purchased

Average Price Paid per Common Share

Total Number of Shares Purchased as Part of Publicly Announced Plans or Programs

Maximum Number (or Approximate Dollar Value) of Shares that May Yet be Purchased under the Plans or Programs

October 1, 2025 – October 31, 2025

November 1, 2025 – November 30, 2025

December 1, 2025 – December 31, 2025

Total

(1) Represents shares of common stock of BXP surrendered by employees to BXP to satisfy such employees’ tax withholding obligations in connection with the vesting of restricted common stock.

BPLP

(a) Each time BXP issues shares of common stock (other than in exchange for common units when such common units are presented for redemption), it contributes the proceeds of such issuance to BPLP in return for an equivalent number of partnership units with rights and preferences analogous to the shares issued. During the three months ended December 31, 2025, in connection with issuances of common stock by BXP pursuant to purchases under the 2021 Plan, BPLP issued an aggregate of 702 common units to BXP. Such units were issued in reliance on an exemption from registration under Section 4(a)(2) of the Securities Act of 1933, as amended.

(b) Not Applicable.

(c) Issuer Purchases of Equity Securities.

Period

Total Number of Units

Purchased

Average Price Paid per Unit

Total Number of Units Purchased as Part of Publicly Announced Plans or Programs

Maximum Number (or Approximate Dollar Value) of Units that May Yet be Purchased

October 1, 2025 – October 31, 2025

November 1, 2025 – November 30, 2025

December 1, 2025 – December 31, 2025

Total

(1) Represents common units previously held by BXP that were redeemed in connection with the surrender of

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shares of restricted common stock of BXP by employees to BXP to satisfy such employees’ tax withholding obligations in connection with the vesting of restricted common stock.

Item 6. Reserved

Not applicable.

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Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

The following discussion should be read in conjunction with the financial statements and notes thereto appearing elsewhere in this report.

Forward Looking Statements

This Annual Report on Form 10-K, including the documents incorporated by reference herein, contain forward-looking statements within the meaning of the federal securities laws, Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). We intend these forward-looking statements to be covered by the safe harbor provisions for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995, and we are including this statement for purposes of complying with those safe harbor provisions, in each case, to the extent applicable. The forward-looking statements are contained principally, but not only, under the captions “Business — Business and Growth Strategies” “ Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations.” We caution investors that forward-looking statements are based on current beliefs, expectations of future events and assumptions made by, and information currently available to, our management. When used, the words “anticipate,” “believe,” “budget,” “could,” “estimate,” “expect,” “intend,” “may,” “might,” “plan,” “project,” “should,” “will,” and similar expressions that do not relate solely to historical matters are intended to identify forward-looking statements. These statements are subject to risks, uncertainties and assumptions and are not guarantees of future performance or occurrences, which may be affected by known and unknown risks, trends, uncertainties and factors that are, in some cases, beyond our control. If one or more of these known or unknown risks or uncertainties materialize, or if underlying assumptions prove incorrect, actual results may differ materially from those expressed or implied by the forward-looking statements. We caution you that, while forward-looking statements reflect our good-faith beliefs when we make them, they are not guarantees of future performance or occurrences and are impacted by actual events when they occur after we make such statements. Accordingly, investors should use caution in relying on forward-looking statements, which are based on results, trends and assumptions at the time they are made, to anticipate future results or trends.

Some of the risks and uncertainties that may cause actual results to differ materially from those expressed or implied by the forward-looking statements include the following risks and uncertainties, among others:

• volatile or adverse economic, capital markets and political conditions, including continued inflation, elevated interest rates, supply chain disruptions, policy changes related to tariffs and prolonged government shutdowns or disruptions, which may directly or indirectly impact us, our current clients and our prospective clients, including their demand for office space, and the costs and availability of construction materials and the economic returns on our construction and development activities;

• volatile or adverse geopolitical conflicts and dislocations in the credit markets could adversely affect economic conditions and/or restrict our access to cost-effective capital, which could have a material adverse effect on our business opportunities, results of operations and financial condition;

• risks associated with the availability and terms of financing, the use of debt to fund acquisitions and developments or refinance existing indebtedness, including the impact of higher interest rates on the cost and/or availability of financing and the use of forward interest rate contracts and derivatives and the effectiveness of such arrangements;

• general risks affecting the real estate industry (including, without limitation, the inability to enter into or renew leases on attractive terms, sustained changes in client preferences and space utilization, dependence on clients’ financial condition, and competition from other developers, owners and operators of real estate);

• failure to integrate acquisitions and developments successfully;

• risks and uncertainties affecting property development and construction;

• the ability of our joint venture partners to satisfy their obligations;

• risks associated with actual or threatened terrorist attacks;

• costs of compliance with the Americans with Disabilities Act and other similar laws;

• potential liability for uninsured losses and environmental contamination;

• risks associated with climate change and severe weather events, as well as the regulatory efforts intended to reduce the effects of climate change;

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• risks associated with our use of AI and cyber security breaches, incidents and compromises, as well as other significant disruptions of our information technology (IT) networks and related systems, which support our operations and our buildings;

• risks associated with legal proceedings and other claims that could result in substantial monetary damages and other costs;

• risks associated with BXP’s potential failure to qualify as a REIT under the Internal Revenue Code of 1986, as amended (the “Code”);

• possible adverse changes in tax and environmental laws;

• the impact of newly adopted accounting principles on our accounting policies and on period-to-period comparisons of financial results;

• risks associated with possible state and local tax audits; and

• risks associated with our dependence on key personnel whose continued service is not guaranteed.

The risks set forth above are not exhaustive. Other sections of this report, including “Part I, Item 1A—Risk Factors,” include additional factors that could adversely affect our business and financial performance. Moreover, we operate in a very competitive and rapidly changing environment. New risk factors emerge from time to time and it is not possible for management to predict all risk factors, nor can we assess the impact of all risk factors on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements. Given these risks and uncertainties, investors should not unduly rely on forward-looking statements as a prediction of actual results. Investors should also refer to our Quarterly Reports on Form 10-Q for future periods and Current Reports on Form 8-K as we file them with the SEC, and to other materials we may furnish to the public from time to time through Current Reports on Form 8-K or otherwise, for a discussion of risks and uncertainties that may cause our actual results, performance or achievements to differ materially from those expressed or implied by forward-looking statements. We expressly disclaim any responsibility to update any forward-looking statements to reflect changes in underlying assumptions or factors, new information, future events, or otherwise, and you should not rely upon these forward-looking statements after the date of this report.

Overview

BXP is one of the largest publicly traded office REITs (based on total market capitalization as of December 31, 2025) in the United States that develops, owns, and manages primarily premier workplaces. Our properties are concentrated in six dynamic gateway markets in the U.S. - Boston, Los Angeles, New York, San Francisco, Seattle and Washington, DC.

We generate revenue and cash primarily by leasing premier workplaces to our clients. We consider premier workplaces to be well-located buildings that are modern structures or have been modernized to compete with newer buildings, are professionally managed and maintained, and offer a number and type of amenities that are in high demand by clients that are focused on the importance of the physical work environment in recruiting and retaining the best and brightest employees. As such, these properties attract creditworthy clients and command upper-tier rental rates in their markets. We do not consider the expression “premier workplaces” a classification of our properties in accordance with any standard listing criteria in the real estate industry. We therefore caution investors that our use and definition of “premier workplaces” may be different than the use and definition of similar expressions and traditional classifications that may be used by other companies.

When making leasing decisions, we consider, among other things, the creditworthiness of the client and the industry in which it conducts business, the length of the lease, the rental rate to be paid at inception and throughout the lease term, the amount of any security deposit or letter of credit posted by the client, the costs of tenant improvement allowances, free rent periods and other landlord concessions, anticipated operating expenses and real estate taxes, the date by which we expect to begin revenue recognition for the lease under GAAP, current and anticipated vacancy in our properties and the market overall (including sublease space), current and expected future demand for the space, the impact of other clients’ expansion rights and general economic factors.

We believe our key competitive advantages are our commitments to the office asset class and to our clients as many competitors have divested from the sector, a strong balance sheet with access to capital in the secured and unsecured debt markets and the private and public equity markets, and the high quality of our portfolio of premier

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workplaces. Our core strategy has always been to develop, acquire and manage premier workplaces in gateway markets with high barriers-to-entry and attractive demand drivers and to focus on executing long-term leases with financially strong clients that are diverse across market sectors. We believe this strategy provides a competitive advantage as our clients are interested in leasing space in vibrant, amenitized and accessible premier workplaces. This interest has accelerated the flight to quality in the office market. Over the past several years, BXP’s experience and performance has diverged from the larger market and media sentiment, as premier workplaces have outperformed the broader office market consistently and substantially in both rental rates achieved and occupancy. We believe this divergence validates our strategy and differentiates BXP from other office companies.

Premier workplaces in our five traditional central business district (“CBD”) markets (Boston, New York, San Francisco, Seattle and Washington, DC) have consistently outperformed the broader office market in those CBDs on several key metrics, including occupancy, net absorption levels, rental rates and landlord concessions. This outperformance is evident in BXP’s portfolio where we derive approximately 90% of our share of annualized rental obligations from predominantly premier workplaces located in CBDs. We define annualized rental obligations as the monthly contractual base rent (excluding percentage rent and rent abatements) and budgeted reimbursements from clients under existing leases as of December 31, 2025, multiplied by twelve. Our share of annualized rental obligations is calculated as the consolidated amount, plus our share of the amount from our unconsolidated joint ventures (calculated based on our economic percentage ownership interest), less our partners’ share of the amount from our consolidated joint ventures (calculated based on the partners’ economic percentage ownership interest). As of December 31, 2025, our CBD assets were 89.8% occupied and 92.5% leased (including vacant space for which we have signed leases that have not yet commenced in accordance with GAAP).

As of December 31, 2025, the weighted-average remaining lease term for (1) our in-place leases, based on square feet, including those signed by our unconsolidated joint ventures but excluding residential units, was approximately 7.9 years, and (2) our 20 largest clients, based on square feet, was approximately 9.8 years. Through year-end 2027, we have relatively low exposure to contractual lease expirations with approximately 7.2% of our share of the square footage of our in-service portfolio expiring.

During the fourth quarter of 2025, BXP continued to successfully execute on the multi-year strategic action plan introduced at our September 2025 Investor Day. The action plan focuses on earnings growth, which we expect will be achieved through a combination of increased occupancy and development deliveries, and reducing leverage through asset sales and retention of cash flow. Our progress reflects steady advancement across each of these key priorities.

Growth in Funds from Operations (“FFO”) per share depends in large part on the success of our leasing activity. Leasing momentum remained strong during the fourth quarter of 2025, as we signed leases for more than 1.8 million square feet.

Consistent with the asset sales program outlined at our September 2025 Investor Day, as of February 20, 2026, BXP completed property sales with an aggregate gross sales price of approximately $1.17 billion. These asset sales enhance balance sheet flexibility and support our capital needs and strategic priorities, and fall into the following categories:

• Land Sales: Multiple land dispositions across our Boston, San Francisco and Washington, DC regions which aggregated a gross sales price of approximately $266.4 million.

• Residential Sales: The sales of Proto in Cambridge, Massachusetts and Signature in Reston, Virginia which aggregated a gross sales price of approximately $407.5 million.

• Non-Strategic Office Sales: The sale of 140 Kendrick Street in Needham, Massachusetts, and BXP’s ownership interests in Gateway Commons in South San Francisco, California and Market Square North in Washington, DC which aggregated a gross sales price of approximately $491.5 million.

Outlook

Leasing conditions across BXP’s portfolio remain constructive. Fourth quarter and full-year 2025 leasing results exceeded expectations, supporting anticipated occupancy gains throughout 2026. While market conditions continue to vary by region, demand remains concentrated in our highest-quality CBD assets, particularly in Midtown Manhattan, the Back Bay of Boston, Reston Town Center, and select submarkets in San Francisco.

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Looking ahead, in-service vacant space leasing and coverage of near-term expirations are expected to be the primary drivers of occupancy and same-store revenue growth. With a manageable level of 2026 expirations, a growing pipeline of active negotiations, and a meaningful number of executed leases scheduled to commence this year, we remain on track to achieve occupancy improvements by year-end 2026, consistent with the targets outlined at our September 2025 Investor Day.

On the supply side, new office construction has effectively halted, improving long-term supply-demand fundamentals across many of our markets. Capital markets sentiment toward the office sector continues to improve, evidenced by increasing private market transaction activity and greater availability of debt and equity capital at more attractive pricing. This backdrop is expected to support both our leasing momentum and continued progress on our strategic asset sales and capital recycling initiatives throughout 2026.

Leasing Activity and Occupancy

Although all of the markets in which we operate still need consistent incremental absorption to constitute a macro recovery, we continue to see pockets of strength where low availability is driving constructive client behavior. As clients choose premier workplaces in sound financial condition with building owners that are committed to their properties for the long term and operated by the best property management teams, we expect to continue to be successful in gaining market share.

In the fourth quarter of 2025, we executed 87 leases totaling more than 1.8 million square feet with a weighted-average lease term of approximately 11.3 years.

At December 31, 2025, BXP’s total in-service portfolio occupancy was 86.7%, an increase of 70 basis points from the third quarter of 2025. BXP’s total portfolio was 89.4% leased (including vacant space for which we have signed leases that have not yet commenced revenue recognition in accordance with GAAP), an increase of 60 basis points from the third quarter of 2025.

An overview of the leasing activity in each of our regions for the three months ended December 31, 2025 is set forth in the table below. Amounts shown are in square feet, except for percentages, and include 100% of the unconsolidated joint venture properties.

Leases commenced (1)

Region

Leases executed (2)

Total

Second generation space vacant < 1 Year

Change in second generation cash rents, net (3)

Occupancy

Leased (4)

Boston

Los Angeles

New York

San Francisco

Seattle

Washington, DC

Total / Weighted Average

(1) Represents space with signed leases for which lease revenue recognition has commenced in accordance with GAAP during the three months ended December 31, 2025.

(2) Represents leases executed during the three months ended December 31, 2025 for which we either (1) commenced lease revenue recognition in such quarter or (2) will commence lease revenue recognition in subsequent quarters, in accordance with GAAP, and includes leases at properties currently under development. The total square feet of leases executed during the three months ended December 31, 2025 for which we recognized lease revenue in the three months ended December 31, 2025 is 275,420.

(3) Represents the increase (decrease) in net rent (gross rent less operating expenses) under the new leases versus expired leases on the 898,799 square feet of second generation leases that had been occupied within the prior 12 months.

(4) Represents signed leases for which lease revenue recognition has commenced in accordance with GAAP and signed leases for vacant space with future commencement dates.

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The table below details the vacancy and leasing activity in our portfolio, including 100% of the unconsolidated joint ventures, that commenced revenue recognition during the year ended December 31, 2025:

Year ended December 31, 2025

(Square Feet)

Vacant space available at the beginning of the period

Vacant space from property dispositions/properties taken out of service (1)

Vacant space from properties placed (and partially placed) in-service (2)

Leases expiring or terminated during the period

Total space available for lease

1 st generation leases (3)

2 nd generation leases with new clients (3)

2 nd generation lease renewals (3)

Total space leased (3)

Vacant space available for lease at the end of the period

Leases executed during the period, in square feet (4)

Second generation leasing information : (5)

Leases commencing during the period, in square feet

Weighted Average Lease Term

89 Months

Weighted Average Free Rent Period

195 Days

Total Transaction Costs Per Square Foot (6)

Increase (Decrease) in Gross Rents (7)

Increase (Decrease) in Net Rents (8)

(1) Total square feet from properties taken out of service during the year ended December 31, 2025 consists of 261,046 square feet at Reston Corporate Center, 211,840 square feet at 1000 Winter Street, 201,634 square feet at Reservoir Place, 102,980 square feet at Market Square North, 89,851 square feet at 140 Kendrick Street and 23,633 square feet at 200 Clarendon Street.

(2) Total square feet from properties placed (and partially placed) in-service during the year ended December 31, 2025 consists of 345,570 square feet at 360 Park Avenue South, 162,274 square feet at 1050 Winter Street and 82,771 square feet at Reston Next Office Phase II.

(3) Represents leases for which lease revenue recognition has commenced in accordance with GAAP during the year ended December 31, 2025.

(4) Represents leases executed during the year ended December 31, 2025 for which we either (1) commenced lease revenue recognition in such quarter or (2) will commence lease revenue recognition in subsequent quarters, in accordance with GAAP, and includes leases at properties currently under development. The total square feet of leases executed during the year ended December 31, 2025 for which we recognized lease revenue in the year ended December 31, 2025 is 886,021.

(5) Second generation leases are defined as leases for space that we have previously leased. Of the 3,945,942 square feet of second generation leases that commenced revenue recognition during the year ended December 31, 2025, leases for 3,067,250 square feet were signed in prior periods.

(6) Total transaction costs include tenant improvements and leasing commissions but exclude free rent concessions and other inducements in accordance with GAAP.

(7) Represents the increase (decrease) in gross rent (base rent plus expense reimbursements) under the new leases versus expired leases on the 2,453,253 square feet of second generation leases that had been occupied within the prior 12 months; excludes leases that management considers temporary because the client is not expected to occupy the space on a long-term basis.

(8) Represents the increase (decrease) in net rent (gross rent less operating expenses) under the new leases versus expired leases on the 2,453,253 square feet of second generation leases that had been occupied within the prior 12 months.

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Investment Activity

In 2025, BXP commenced construction on 343 Madison Avenue in New York City, New York. 343 Madison Avenue will be a highly amenitized, sustainably designed, 46-story, 930,000 square foot premier workplace located on one of the most desirable office development sites in Manhattan with direct access to Grand Central Station. The project is 29% pre-leased as of February 20, 2026, and BXP is in active discussions with other prospective clients.

BXP fully placed three development properties into service in 2025, reflecting continued execution on its development pipeline and the successful delivery of premier workplace assets:

• 1050 Winter Street, an approximately 162,000 square foot office building located in the urban edge of Boston, Massachusetts. As of February 20, 2026, the project is 100% leased.

• Reston Next Office Phase II, an approximately 87,000 square foot boutique premier workplace located in Reston, Virginia. As of February 20, 2026, the project is 92% leased.

• 360 Park Avenue South, an approximately 448,000 square foot premier workplace located in New York City, New York, in which we have an approximately 71% ownership interest. As of February 20, 2026, the project is 59% leased.

For descriptions of significant transactions that we completed during 2025, see “ Item 1. Business—Transactions During 2025 .”

Critical Accounting Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America, or GAAP, requires management to use judgment in the application of accounting policies, including making estimates and assumptions. We base our estimates on historical experience and on various other assumptions believed to be reasonable under the circumstances. These judgments affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the dates of the financial statements and the reported amounts of revenue and expenses during the reporting periods. If our judgment or interpretation of the facts and circumstances relating to various transactions had been different, it is possible that different accounting policies would have been applied resulting in a different presentation of our financial statements. From time to time, we evaluate our estimates and assumptions. In the event estimates or assumptions prove to be different from actual results, adjustments are made in subsequent periods to reflect more current information. Our significant accounting policies, which utilize these critical accounting estimates, are described in Note 2 to our Consolidated Financial Statements.

We consider our critical accounting estimates to be those used in the determination of the reported amounts and disclosure related to the following:

• Purchase price allocations,

• Impairment and

• Impairment related to unconsolidated joint ventures.

Each of the above critical accounting estimates is described in more detail below.

Real Estate

Purchase Price Allocations

We assess the fair value of acquired tangible and intangible assets (including land, buildings, tenant improvements, “above-” and “below-market” leases, leasing and assumed financing origination costs, acquired in-place leases, other identified intangible assets and assumed liabilities (including ground leases)) and allocate the purchase price to the acquired assets and assumed liabilities, including land and buildings as if vacant. We assess fair value based on estimated cash flow projections that utilize discount and/or capitalization rates that we deem appropriate, as well as available market information. Estimates of future cash flows are based on a number of factors including the historical operating results, known and anticipated trends, and market and economic conditions.

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The fair value of the tangible assets of an acquired property considers the value of the property as if it were vacant. We also consider an allocation of purchase price of other acquired intangibles, including acquired in-place leases that may have a customer relationship intangible value, including (but not limited to) the nature and extent of the existing relationship with the clients, the clients’ credit quality and expectations of lease renewals. Based on our acquisitions to date, our allocation to customer relationship intangible assets has been immaterial.

We record acquired “above-” and “below-market” leases at their fair values (using a discount rate which reflects the risks associated with the leases acquired) equal to the difference between (1) the contractual amounts to be paid pursuant to each in-place lease and (2) management’s estimate of fair market lease rates for each corresponding in-place lease, measured over a period equal to the remaining term of the lease for above-market leases and the initial term plus the term of any below-market fixed rate renewal options for below-market leases. Acquired “above-” and “below-market” lease values have been reflected within Prepaid Expenses and Other Assets and Other Liabilities, respectively, in our Consolidated Balance Sheets. Other intangible assets acquired include amounts for in-place lease values that are based on our evaluation of the specific characteristics of each client’s lease. Factors to be considered include estimates of carrying costs during hypothetical expected lease-up periods considering current market conditions, and costs to execute similar leases. In estimating carrying costs, we include real estate taxes, insurance and other operating expenses and estimates of lost rentals at market rates during the expected lease-up periods, depending on local market conditions. In estimating costs to execute similar leases, we consider leasing commissions, legal and other related expenses.

During the year ended December 31, 2025, we completed the acquisition of 2100 M Street, located in Washington, DC, for a purchase price, including transaction costs, of approximately $55.9 million. This transaction was accounted for as an asset acquisition, and the purchase price was allocated based on the relative fair values of the assets acquired and liabilities assumed (See Note 3 to the Consolidated Financial Statements).

Impairment

Management reviews its long-lived assets for indicators of impairment following the end of each quarter and when events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. This evaluation of long-lived assets is dependent on a number of factors, including when there is an event or adverse change in the operating performance of the long-lived asset or a current expectation that, more likely than not, a long-lived asset will be sold or otherwise disposed of significantly before the end of its previously estimated useful life or hold period. An impairment loss is recognized if the carrying amount of an asset is not recoverable and exceeds its fair value. The evaluation of anticipated cash flows is subjective and is based in part on assumptions regarding anticipated hold periods, future occupancy, future rental rates, future capital requirements, discount rates and capitalization rates. Any or all of such assumptions could differ materially from actual results in future periods. Because cash flows on properties considered to be “long-lived assets to be held and used” are considered on an undiscounted basis to determine whether an asset may be impaired, our established strategy of holding properties over the long term directly decreases the likelihood of recording an impairment loss. If our hold strategy changes or market conditions otherwise dictate a shorter hold period, an impairment loss may be recognized and such loss could be material. If we determine that an impairment has occurred, the affected assets must be reduced to their fair value. During the year ended December 31, 2025, in conjunction with our strategy to sell non-core assets , we evaluated the consolidated properties approved by BXP’s Board of Directors (or a committee thereof) for sale to third-parties, which resulted in recognized impairment losses of approximately $85.8 million and $82.9 million for BXP and BPLP, respectively (See Note 3 to the Consolidated Financial Statements).

Unconsolidated Joint Ventures

As of December 31, 2025, the net carrying amounts of our investments in unconsolidated joint ventures was approximately $983.7 million, which includes investments with deficit balances aggregating approximately $15.6 million included within Other Liabilities in our Consolidated Balance Sheets.

Impairment

Investments in unconsolidated joint ventures are reviewed for indicators of impairment on a quarterly basis and we record impairment charges when events or circumstances change indicating that a decline in the fair values below the carrying amounts has occurred and such decline is other-than-temporary. This evaluation of the investments in unconsolidated joint ventures is dependent on a number of factors, including the performance of each investment, the intent and ability to retain each investment for a period of time to allow for anticipated recovery in market value, and market conditions. We will record an impairment charge if we determine that a decline in the fair value below the carrying amount of an investment in an unconsolidated joint venture is other-than-temporary. The fair value could be calculated by using a pending offer from a third-party or discounted cash flows, which are

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estimates based, in part, on assumptions regarding future occupancy, future rental rates, future capital requirements, debt interest rates and availability, third party offers, discount rates and capitalization rates that could differ materially from actual results in future periods. Such evaluation of key impairment indicators, including a pending offer from a third-party, resulted in our determination that the decline in value for the joint venture that owns Gateway Commons was other-than-temporary. As a result, during the year ended December 31, 2025, we recognized an other-than-temporary impairment loss on our investment in Gateway Commons of approximately $145.1 million (See Notes 6 and 17 to the Consolidated Financial Statements).

Income Taxes

Our accounting policies related to income tax are described in Note 2 to our Consolidated Financial Statements.

BXP

The net difference between the tax basis and the reported amounts of BXP’s assets and liabilities was approximately $653.1 million and $1.6 billion as of December 31, 2025 and 2024, respectively, which was primarily related to the difference in basis of contributed property and accrued rental income.

Certain entities included in BXP’s Consolidated Financial Statements are subject to certain state and local taxes. These taxes are recorded as operating expenses in the accompanying Consolidated Financial Statements.

The following table reconciles GAAP net income attributable to BXP, Inc. to taxable income:

For the year ended December 31,

(in thousands)

Net income attributable to BXP, Inc.

Straight-line rent and net “above-” and “below-market” rent adjustments

Book/Tax differences from depreciation and amortization

Book/Tax differences from interest expense

Book/Tax differences on gains/(losses) from capital transactions

Book/Tax differences from stock-based compensation

Tangible Property Regulations

Other book/tax differences, net

Taxable income

BPLP

The net difference between the tax basis and the reported amounts of BPLP’s assets and liabilities was approximately $1.7 billion and $2.7 billion as of December 31, 2025 and 2024, respectively, which was primarily related to the difference in basis of contributed property and accrued rental income.

Certain entities included in BPLP’s Consolidated Financial Statements are subject to certain state and local taxes. These taxes are recorded as operating expenses in the accompanying Consolidated Financial Statements.

The following table reconciles GAAP net income attributable to Boston Properties Limited Partnership to taxable income:

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For the year ended December 31,

(in thousands)

Net income attributable to Boston Properties Limited Partnership

Straight-line rent and net “above-” and “below-market” rent adjustments

Book/Tax differences from depreciation and amortization

Book/Tax differences from interest expense

Book/Tax differences on gains/(losses) from capital transactions

Book/Tax differences from stock-based compensation

Tangible Property Regulations

Other book/tax differences, net

Taxable income

Results of Operations

At December 31, 2025 and 2024, we owned or had joint venture interests in a portfolio of 179 and 185 commercial real estate properties, respectively (in each case, the “Total Property Portfolio”). As a result of changes within our Total Property Portfolio, the financial data presented below shows significant changes in revenue and expenses from period-to-period. Accordingly, we do not believe that our period-to-period financial data with respect to the Total Property Portfolio provides a complete understanding of our operating results. Therefore, the comparison of operating results for the years ended December 31, 2025 and 2024 shows separately the changes attributable to the properties that were owned by us and in-service throughout each period compared (the “Same Property Portfolio”) and the changes attributable to the properties included in the Acquired, Placed In-Service, In or Held for Development or Redevelopment or Sold Portfolios.

In our analysis of operating results, particularly to make comparisons of Net Operating Income (“NOI”) between periods more meaningful, it is important to provide information for properties that were in-service and owned by us throughout each period presented. We refer to properties acquired or placed in-service prior to the beginning of the earliest period presented and owned by us and in-service through the end of the latest period presented as our Same Property Portfolio. The Same Property Portfolio therefore excludes properties acquired, placed in-service or in or held for development or redevelopment after the beginning of the earliest period presented or disposed of prior to the end of the latest period presented.

NOI is a non-GAAP financial measure equal to net income attributable to BXP, Inc. and net income attributable to Boston Properties Limited Partnership, as applicable, the most directly comparable GAAP financial measures, plus (1) net income attributable to noncontrolling interests, interest expense, loss from early extinguishment of debt, impairment losses, loss on sales-type lease, loss from unconsolidated joint ventures, depreciation and amortization expense, transaction costs, payroll and related costs from management services contracts and corporate general and administrative expense less (2) unrealized gain (loss) on non-real estate investments, gains from investments in securities, interest and other income (loss), gains on sales of real estate, direct reimbursements of payroll and related costs from management services contracts and development and management services revenue. We use NOI internally as a performance measure and believe it provides useful information to investors regarding our results of operations and financial condition because, when compared across periods, it reflects the impact on operations from trends in occupancy rates, rental rates, operating costs and acquisition and development activity on an unleveraged basis, providing perspective not immediately apparent from net income attributable to BXP, Inc. and net income attributable to Boston Properties Limited Partnership. For example, interest expense is not necessarily linked to the operating performance of a real estate asset and is often incurred at the corporate level as opposed to the property level. Similarly, interest expense may be incurred at the property level even though the financing proceeds may be used at the corporate level (e.g., used for other investment activity). In addition, depreciation and amortization expense, because of historical cost accounting and useful life estimates, may distort operating performance measures at the property level. NOI presented by us may not be comparable to NOI reported by other REITs or real estate companies that define NOI differently.

We believe that in order to understand our operating results, NOI should be examined in conjunction with net income attributable to BXP, Inc. and net income attributable to Boston Properties Limited Partnership as presented in our Consolidated Financial Statements. NOI should not be considered as a substitute for net income attributable

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to BXP, Inc. or net income attributable to Boston Properties Limited Partnership (determined in accordance with GAAP) or any other GAAP financial measures and should only be considered together with and as a supplement to our financial information prepared in accordance with GAAP.

Gains on sales of real estate, impairment losses and depreciation expense may differ between BXP and BPLP as a result of previously applied acquisition accounting by BXP for the issuance of common stock in connection with non-sponsor redemptions of common units of limited partnership interest of BPLP (“OP Units”). This accounting resulted in a step-up of the real estate assets at BXP that was allocated to certain properties. The difference between the real estate assets of BXP as compared to BPLP for certain properties having an allocation of the real estate step-up will result in a corresponding difference in depreciation expense, impairment losses and gains on sales of real estate upon the sale of these properties. For additional information see the Explanatory Note that immediately follows the cover page of this Annual Report on Form 10-K.

Results of Operations for the Years Ended December 31, 2025 and 2024

This section of this Form 10-K generally discusses 2025 and 2024 items and year-to-year comparisons between 2025 and 2024. Discussions of 2023 items and year-to-year comparisons between 2024 and 2023 that are not included in this Form 10-K can be found in “ Management’s Discussion and Analysis of Financial Condition and Results of Operation s” in Part II, Item 7 of our Annual Report on Form 10-K for the year ended December 31, 2024, which was filed with the SEC on February 27, 2025.

Net income attributable to BXP, Inc. and net income attributable to Boston Properties Limited Partnership increased by approximately $262.5 million and $297.6 million, respectively, for the year ended December 31, 2025 compared to 2024, as set forth in the following tables and for the reasons discussed below under the heading “ Comparison of the year ended December 31, 2025 to the year ended December 31, 2024” within “Item 7—Management’s Discussion and Analysis of Financial Condition and Results of Operations.”

The following are reconciliations of (1) Net Income Attributable to BXP, Inc. to NOI and (2) Net Income Attributable to Boston Properties Limited Partnership to NOI for the years ended December 31, 2025 and 2024. For a detailed discussion of NOI, including the reasons management believes NOI is useful to investors, see page 60 .

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BXP

Year ended December 31,

Increase/

(Decrease)

Change

(in thousands)

Net Income Attributable to BXP, Inc.

Net Income Attributable to Noncontrolling Interests:

Noncontrolling interest—common units of the Operating Partnership

Noncontrolling interests in property partnerships

Net Income

Other Expenses:

Add:

Interest expense

Loss from early extinguishment of debt

Impairment losses

Loss on sales-type lease

Loss from unconsolidated joint ventures

Other Income:

Less:

Unrealized gain (loss) on non-real estate investments

Gains from investments in securities

Interest and other income (loss)

Gains on sales of real estate

Other Expenses:

Add:

Depreciation and amortization expense

Transaction costs

Payroll and related costs from management services contracts

General and administrative expense

Other Revenue:

Less:

Direct reimbursements of payroll and related costs from management services contracts

Development and management services revenue

Net Operating Income (“NOI”)

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BPLP

Year ended December 31,

Increase/

(Decrease)

Change

(in thousands)

Net Income Attributable to Boston Properties Limited Partnership

Net Income Attributable to Noncontrolling Interests:

Noncontrolling interests in property partnerships

Net Income

Other Expenses:

Add:

Interest expense

Loss from early extinguishment of debt

Impairment losses

Loss on sales-type lease

Loss from unconsolidated joint ventures

Other Income:

Less:

Unrealized gain (loss) on non-real estate investments

Gains from investments in securities

Interest and other income (loss)

Gains on sales of real estate

Other Expenses:

Add:

Depreciation and amortization expense

Transaction costs

Payroll and related costs from management services contracts

General and administrative expense

Other Revenue:

Less:

Direct reimbursements of payroll and related costs from management services contracts

Development and management services revenue

Net Operating Income (“NOI”)

Comparison of the year ended December 31, 2025 to the year ended December 31, 2024

The table below shows selected operating information for the Same Property Portfolio and the Total Property Portfolio. The Same Property Portfolio consists of 142 properties totaling approximately 40.0 million net rentable square feet, excluding unconsolidated joint ventures. The Same Property Portfolio includes properties acquired or placed in-service on or prior to January 1, 2024 and owned and in service through December 31, 2025. The Total Property Portfolio includes the effects of the other properties either acquired, placed in-service, in or held for development or redevelopment after January 1, 2024 or disposed of on or prior to December 31, 2025. This table includes a reconciliation from the Same Property Portfolio to the Total Property Portfolio by also providing information for the years ended December 31, 2025 and 2024 with respect to the properties that were acquired, placed in-service, in or held for development or redevelopment, or sold.

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Same Property Portfolio

Properties Acquired Portfolio

Properties

Placed In-Service

Portfolio

Properties in or Held for Development or Redevelopment Portfolio

Properties Sold Portfolio

Total Property Portfolio

Increase/

(Decrease)

Change

Increase/

(Decrease)

Change

(dollars in thousands)

Rental Revenue: (1)

Lease Revenue (Excluding Termination Income)

Termination Income

Lease Revenue

Parking and Other

Total Rental Revenue (1)

Real Estate Operating Expenses

Net Operating Income (Loss), Excluding Residential and Hotel

Residential Net Operating Income (2)

Hotel Net Operating Income (2)

Net Operating Income (Loss)

(1) Rental Revenue is equal to Revenue less Development and Management Services Revenue and Direct Reimbursements of Payroll and Related Costs from Management Services Revenue per the Consolidated Statements of Operations, excluding the residential and hotel revenue that is noted below. We use Rental Revenue internally as a performance measure and in calculating other non-GAAP financial measures (e.g., NOI), which provide investors with information regarding our performance that is not immediately apparent from the most directly comparable GAAP measures and allows investors to compare operating performance between periods.

(2) For a detailed discussion of NOI, including the reasons management believes NOI is useful to investors, see page 60. Residential Net Operating Income for the year ended December 31, 2025 and 2024 is comprised of Residential Revenue of $50,543 and $49,508 less Residential Expenses of $26,188 and $23,472, respectively. Hotel Net Operating Income for the year ended December 31, 2025 and 2024 is comprised of Hotel Revenue of $49,996 and $51,224 less Hotel Expenses of $35,599 and $35,288, respectively, per the Consolidated Statements of Operations.

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Same Property Portfolio

Lease Revenue (Excluding Termination Income)

Lease revenue (excluding termination income) from the Same Property Portfolio increased by approximately $43.5 million for the year ended December 31, 2025 compared to 2024. The increase was a result of our average revenue per square foot increasing by approximately $1.70, contributing approximately $57.3 million, partially offset by approximately $13.8 million due to our average occupancy decreasing from 89.1% to 88.7%.

Termination Income

Termination income increased by approximately $2.6 million for the year ended December 31, 2025 compared to 2024.

Termination income for the year ended December 31, 2025 related to 14 clients across the Same Property Portfolio and totaled approximately $11.3 million.

Termination income for the year ended December 31, 2024 related to 29 clients across the Same Property Portfolio and totaled approximately $8.7 million.

Parking and Other Revenue

Parking and other revenue increased by approximately $8.3 million for the year ended December 31, 2025 compared to 2024. Parking and other revenue increased by approximately $1.8 million and $6.5 million, respectively. The increase in parking revenue was primarily due to an increase in monthly parking. The increase in other revenue was primarily associated with an increase in insurance proceeds.

Real Estate Operating Expenses

Real estate operating expenses from the Same Property Portfolio increased by approximately $39.5 million, or 3.3%, for the year ended December 31, 2025 compared to 2024, due primarily to increases in (1) repairs and maintenance of approximately $18.7 million, or 9.2%, (2) utilities of approximately $17.8 million, or 14.1%, and (3) other real estate operating expenses of approximately $3.0 million, or 0.3%. The increase in repairs and maintenance was primarily in the New York region. The increase in utilities was primarily in the Boston region.

Properties Acquired Portfolio

The table below lists the properties acquired between January 1, 2024 and December 31, 2025. Rental revenue and real estate operating expenses increased by approximately $0.2 million and $1.0 million, respectively, for the year ended December 31, 2025 compared to 2024, as detailed below.

Square Feet

Rental Revenue

Real Estate Operating Expenses

Name

Date acquired

Change

Change

(dollars in thousands)

901 New York Avenue

January 8, 2024

Properties Placed In-Service Portfolio

The table below lists the properties that were placed in-service or partially placed in-service between January 1, 2024 and December 31, 2025. Rental revenue and real estate operating expenses from our Properties Placed In-Service Portfolio increased by approximately $46.0 million and $8.0 million, respectively, for the year ended December 31, 2025 compared to 2024, as detailed below.

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Quarter Initially Placed In-Service

Quarter Fully Placed In-Service

Rental Revenue

Real Estate Operating Expenses

Name

Square Feet

Change

Change

(dollars in thousands)

180 CityPoint

Third Quarter, 2023

Third Quarter, 2024

103 CityPoint

Fourth Quarter, 2023

Fourth Quarter, 2024

760 Boylston Street

Second Quarter, 2024

Second Quarter, 2024

Reston Next Office Phase II

Third Quarter, 2024

Third Quarter, 2025

300 Binney Street

Fourth Quarter, 2024

Fourth Quarter, 2024

Reston Next Retail (1)

First Quarter, 2025

1050 Winter Street

Second Quarter, 2025

Third Quarter, 2025

(1) On January 16, 2026, Reston Next Retail was fully placed in-service.

Properties in or Held for Development or Redevelopment Portfolio

The table below lists the properties that were in or held for development or redevelopment between January 1, 2024 and December 31, 2025. Rental revenue and real estate operating expenses from our Properties in or Held for Development or Redevelopment Portfolio decreased by approximately $32.3 million and $2.4 million, respectively, for the year ended December 31, 2025 compared to 2024, as detailed below.

Date Commenced Held for Development / Redevelopment

Rental Revenue

Real Estate Operating Expenses

Name

Square Feet

Change

Change

(dollars in thousands)

Held for Development or Redevelopment (1)

Lexington Office Park

March 31, 2023

Shady Grove Innovation District (2)

March 31, 2024

1000 & 1100 Winter Street (3)

December 31, 2025

Kingstowne One

September 30, 2024

Reston Corporate Center

January 1, 2025

Reservoir Place (4)

March 31, 2025

Redevelopment

171 Dartmouth Street

March 28, 2024

(1) These properties are no longer considered “in-service” because each property’s occupied percentage is less than 50% and we anticipate a future development/redevelopment of the property. A property will be considered held for development or redevelopment until the last client has vacated the property and the property is no longer revenue producing.

(2) This portion of Shady Grove Innovation District is comprised of two buildings, 2098 Gaither Road and 15825 Shady Grove Road.

(3) Rental revenue for the year ended December 31, 2024 includes approximately $6.5 million of termination income.

(4) Reservoir Place is an approximately 526,000 square foot office building, of which approximately 165,000 square feet remains in-service. Rental revenue for the year ended December 31, 2024 includes approximately $0.7 million of termination income.

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Properties Sold Portfolio

The table below lists the properties we sold between January 1, 2024 and December 31, 2025. Rental revenue from our Properties Sold Portfolio decreased by approximately $1.2 million and real estate operating expenses increased by approximately $1.8 million for the year ended December 31, 2025 compared to 2024, as detailed below.

Rental Revenue

Real Estate Operating Expenses

Name

Date Sold

Property Type

Square Feet

Change

Change

(dollars in thousands)

Office/Land

17 Hartwell Avenue (1)

June 27, 2025

Office

Almaden Boulevard

October 17, 2025

Land

Land Parcels at Broad Run

December 1, 2025

Land

3625 Peterson Way

December 11, 2025

Land

140 Kendrick Street

December 17, 2025

Office

Total Office/Land

Residential

Proto Kendall Square

December 18, 2025

Residential

Signature at Reston Town Center

December 19, 2025

Residential

Total Residential

(1) During the year ended December 31, 2024, this property was removed from our “in-service” properties listing and classified as held for redevelopment (See Notes 3 and 6 to the Consolidated Financial Statements).

Residential Net Operating Income

Net operating income for our residential same properties decreased by approximately $0.2 million for the year ended December 31, 2025 compared to 2024.

The following reflects our occupancy and rate information, by region, for our residential same properties for the year ended December 31, 2025 and 2024.

Average Monthly Rental Rate (1)

Average Rental Rate Per Occupied Square Foot

Average Physical Occupancy (2)

Average Economic Occupancy (3)

Region

Change (%)

Change (%)

Change (%)

Change (%)

Boston

San Francisco

(1) Average Monthly Rental Rate is calculated as the average of the quotients obtained by dividing (A) rental revenue as determined in accordance with GAAP, by (B) the number of occupied units for each month within the applicable fiscal period.

(2) Average Physical Occupancy is defined as (1) the average number of occupied units divided by (2) the total number of units, expressed as a percentage.

(3) Average Economic Occupancy is defined as (1) total possible revenue less vacancy loss divided by (2) total possible revenue, expressed as a percentage. Total possible revenue is determined by valuing average occupied units at contract rates and average vacant units at Market Rents. Vacancy loss is determined by valuing vacant units at current Market Rents. By measuring vacant units at their Market Rents, Average Economic Occupancy takes into account the fact that units of different sizes and locations within a residential property have different economic impacts on a residential property’s total possible gross revenue. Market Rents used by us in calculating Economic Occupancy are based on the current market rates set by the managers of our residential properties based on their experience in renting their residential property’s units and publicly available market data. Actual market rents and trends in such rents for a region as reported by others may vary materially from Market Rents used by us. Market Rents for a period are based on the average Market Rents during that period and do not reflect any impact for cash concessions.

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Hotel Net Operating Income

The Boston Marriott Cambridge hotel had net operating income of approximately $14.4 million for the year ended December 31, 2025, representing a decrease of approximately $1.5 million compared to the year ended December 31, 2024.

The following reflects our occupancy and rate information for the Boston Marriott Cambridge hotel for the year ended December 31, 2025 and 2024.

Change (%)

Occupancy

Average daily rate

REVPAR

Other Operating Revenue and Expense Items

Development and Management Services Revenue

Development and management services revenue increased by approximately $8.5 million for the year ended December 31, 2025 compared to 2024. Development services revenue and management services revenue increased by approximately $3.8 million and $4.7 million, respectively. The increase in development services revenue was primarily related to an increase in fees associated with a tenant improvement project in the Boston region. The increase in management services revenue was primarily related to leasing commissions earned from an unconsolidated joint venture and a third-party managed building in the New York region.

General and Administrative Expense

General and administrative expense increased by approximately $8.8 million for the year ended December 31, 2025 compared to 2024 primarily due to increases in compensation expense and other general and administrative expenses of approximately $7.0 million and $1.8 million, respectively. The increase in compensation expense was partially due to an approximately $2.3 million increase in health insurance costs and an approximately $1.1 million increase in the value of our deferred compensation plan.

Wages directly related to the development of rental properties are capitalized and included in real estate assets on our Consolidated Balance Sheets and amortized over the useful lives of the applicable asset or lease term. Capitalized wages for each of the year ended December 31, 2025 and 2024 were approximately $17.0 million and $17.2 million, respectively. These costs are not included in the general and administrative expenses discussed above.

Transaction Costs

Transaction costs increased by approximately $1.1 million for the year ended December 31, 2025 compared to 2024. In general, transaction costs relating to the formation of new joint ventures and the pursuit of other transactions are expensed as incurred.

Depreciation and Amortization Expense

Depreciation and amortization expense increased by approximately $24.9 million for the year ended December 31, 2025 compared to 2024, for BXP and BPLP, as detailed below (in thousands).

Portfolio

BXP

BPLP

Change

Change

Same Property Portfolio

Properties Acquired Portfolio

Properties Placed In-Service Portfolio

Properties in or Held for Development or Redevelopment Portfolio

Properties Sold Portfolio

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Direct Reimbursements of Payroll and Related Costs From Management Services Contracts and Payroll and Related Costs From Management Service Contracts

We have determined that amounts reimbursed for payroll and related costs received from third parties in connection with management services contracts should be reflected on a gross basis instead of on a net basis as we have determined that we are the principal under these arrangements. We anticipate that these two financial statement line items will generally offset each other.

Other Income and Expense Items

Loss from Unconsolidated Joint Ventures

For the year ended December 31, 2025 compared to 2024, loss from unconsolidated joint ventures decreased by approximately $239.6 million primarily due to (1) an approximately $196.2 million decrease in the non-cash impairment losses that were recognized at several of our joint ventures and (2) a decrease in depreciation expense as a result of the impairment losses recognized, partially offset by an increase in gains on sales of approximately $32.0 million (See Note 6 to the Consolidated Financial Statements).

Gains on Sales of Real Estate

Gains on sales of real estate increased by approximately $176.1 million and $178.7 million for the year ended December 31, 2025 compared to 2024, for BXP and BPLP, respectively, as detailed below.

Property

Location

Date Disposed

Square Feet

Gross Sales Price

Net Cash Proceeds

BXP Gain (1)

BPLP Gain (1)

(dollars in thousands)

Land:

17 Hartwell Avenue (2)

Lexington, MA

June 27, 2025

Land Parcels at New Dominion Technology Park

Fairfax County, VA

October 15, 2025

Almaden Boulevard

San Jose, CA

October 17, 2025

Land Parcels at Broad Run

Loudoun County, VA

December 1, 2025

3625 Peterson Way

San Jose, CA

December 11, 2025

Residential:

Proto Kendall Square

Cambridge, MA

December 18, 2025

Signature at Reston Town Center

Reston, VA

December 19, 2025

Office:

140 Kendrick Street

Needham, MA

December 17, 2025

Total Dispositions

(1) Excludes approximately $1.7 million of gains for each of BXP and BPLP, which are primarily related to sales that occurred in prior periods. With the exception of Almaden Boulevard, the fair value of the real estate disposed exceeded the carrying value (see “ Impairment Losses ” below). During the year ended December 31, 2024, gains on sales of real estate related to prior period sales and totaled approximately $0.6 million for BXP and BPLP.

(2) See Notes 3 and 6 to the Consolidated Financial Statements.

Interest and Other Income (Loss)

Interest and other income (loss) decreased by approximately $24.4 million for the year ended December 31, 2025 compared to 2024, due primarily to a decrease in our outstanding cash balances and corresponding lower interest income, an approximately $5.8 million reserve related to the unpaid default interest on one of our Related Party Notes Receivable (See Note 16 to the Consolidated Financial Statements), partially offset by an

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approximately $1.3 million decrease in the current expected credit loss allowance related to the refinancing of the related party note receivable for 3 Hudson Boulevard (See Note 6 to the Consolidated Financial Statements).

Gains from Investments in Securities

Gains from investments in securities for the year ended December 31, 2025 and 2024 related to investments that we have made to reduce our market risk relating to deferred compensation plans that we maintain for BXP’s officers and former non-employee directors. Under their respective deferred compensation plans, eligible officers and non-employee directors are permitted to defer a portion of their current compensation on a pre-tax basis and receive a tax-deferred return on the amounts deferred based on the performance of specific investments selected by participating officers and non-employee directors. In order to reduce our market risk relating to these plans, we typically acquire, in a separate account that is not restricted as to its use, similar or identical investments as those selected by each officer or non-employee director. This enables us to generally match our liabilities to participants under our deferred compensation plans with equivalent assets and thereby limit our market risk. The performance of these investments is recorded as gains from investments in securities. During the years ended December 31, 2025 and 2024, we recognized gains of approximately $5.5 million and $4.4 million, respectively, on these investments. By comparison, our general and administrative expense decreased by approximately $5.5 million and $4.4 million during the years ended December 31, 2025 and 2024, respectively, as a result of decreases in our liability under our deferred compensation plans that was associated with the performance of the specific investments selected by participating officers and former non-employee directors of BXP.

Unrealized Gain (Loss) on Non-Real Estate Investments

We invest in non-real estate investments, which primarily consist of environmentally-focused investment funds. During the years ended December 31, 2025 and 2024, we recognized an unrealized gain (loss) of approximately $(0.3) million and $0.5 million, respectively, due to the observable changes in the fair value of the investments.

Loss on Sales-Type Lease

During the year ended December 31, 2025, we recognized approximately $2.5 million in additional costs, which had previously been contingent, related to a ground lease for land at our Reston Next property located in Reston, Virginia. We entered into the ground lease in 2020 with a third-party hotel developer and amended it in 2022. The amendment resulted in the derecognition of the assets related to the ground lease and the classification of the ground lease as a sales-type lease resulting in the recognition of a gain on sales-type lease of approximately $10.1 million.

Impairment Losses

Impairment losses increased by approximately $72.2 million and $69.3 million for the year ended December 31, 2025 compared to 2024, for BXP and BPLP, respectively. During the year ended December 31, 2025, in conjunction with our strategy to sell non-core assets, we evaluated the properties approved by BXP’s Board of Directors (or a committee thereof) for sale to third-parties which resulted in recognized impairment losses (See Note 2 to the Consolidated Financial Statements), as detailed below (in thousands):

Property

Location

Property Type

BXP

BPLP

Shady Grove - Parcel 1 (1)

Rockville, MD

Land

Almaden Boulevard

San Jose, CA

Land

1330 Connecticut Avenue

Washington, DC

Office

North First Business Park (2)

San Jose, CA

Office

Shady Grove – Parcel 3

Rockville, MD

Land

Springfield Metro Center

Springfield, VA

Land

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(1) Sold on February 5, 2026, see Note 17 to the Consolidated Financial Statements.

(2) Sold on January 14, 2026, see Note 17 to the Consolidated Financial Statements.

Loss From Early Extinguishment of Debt

On March 28, 2025, BPLP amended and restated its revolving credit agreement (See Note 7 to the Consolidated Financial Statements) . As a result of the amendment and restatement, during the year ended December 31, 2025, we recognized a loss from early extinguishment of debt of approximately $0.3 million related to unamortized origination costs.

Interest Expense

Interest expense increased by approximately $8.0 million for the year ended December 31, 2025 compared to 2024, as detailed below.

Component

Change in interest expense for the year ended December 31, 2025 compared to December 31, 2024

(in thousands)

Increases to interest expense due to:

Issuance of $850 million in aggregate principal of 5.750% senior notes due 2035 on August 26, 2024

Unsecured commercial paper

Increase in interest due to finance leases

Issuance of $1.0 billion in aggregate principal of 2.000% exchangeable senior notes due 2030 on September 29, 2025 (1)

Increase in interest associated with unsecured term loans and the unsecured credit facility, net (2)

Total increases to interest expense

Decreases to interest expense due to:

Repayment of $850 million in aggregate principal of the 3.200% senior notes due 2025 on January 15, 2025

Mortgage loan financings (2)

Increase in capitalized interest related to development projects

Redemption of $700 million in aggregate principal of 3.800% senior notes due 2024 on February 1, 2024

Other interest expense (excluding senior notes)

Amortization expense of financing fees

Total decreases to interest expense

Total change in interest expense

(1) See Note 7 to the Consolidated Financial Statements.

(2) Includes, if applicable, fair value and swap adjustments (See Note 8 to the Consolidated Financial Statements).

Interest expense directly related to the development of rental properties is capitalized and included in real estate assets on our Consolidated Balance Sheets and amortized over the useful lives of the real estate or lease term. As portions of properties are placed in-service, we cease capitalizing interest on that portion and interest is then expensed. Interest capitalized for the year ended December 31, 2025 and 2024 was approximately $50.6 million and $42.0 million, respectively. These costs are not included in the interest expense referenced above.

At December 31, 2025, our variable rate debt consisted of (1) BPLP’s $2.95 billion unsecured credit facility (“2025 Credit Facility”) and (2) BPLP’s $750.0 million unsecured commercial paper program (“Commercial Paper Program”). The 2025 Credit Facility consists of (1) a revolving line of credit (the “Revolving Facility”) of $2.25 billion and (2) an unsecured term loan facility (the “Term Loan Facility”) of $700.0 million. As of December 31, 2025, there

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were $700.0 million and $750.0 million outstanding under the 2025 Credit Facility and Commercial Paper Program, respectively.

In addition, we have a $100.0 million unsecured term loan facility (“2024 Unsecured Term Loan”) and an aggregate of $800.0 million of mortgage notes collateralized by Santa Monica Business Park and the 325 Main Street, 355 Main Street, 90 Broadway and Cambridge East Garage (also known as Kendall Center Green Garage) properties that bear interest at variable rates, which have all been hedged with interest rate swaps to fix SOFR for all or a portion of the applicable debt term.

For a summary of our consolidated debt as of December 31, 2025 refer to the heading “ Liquidity and Capital Resources—Debt” within “ Item 7—Management’s Discussion and Analysis of Financial Condition and Results of Operations. ”

Noncontrolling Interests in Property Partnerships

Noncontrolling interests in property partnerships increased by approximately $7.7 million for the year ended December 31, 2025 compared to 2024, as detailed below.

Property

Noncontrolling Interests in Property Partnerships for the year ended December 31,

Change

(in thousands)

767 Fifth Avenue (the General Motors Building)

7 Times Square (1)

601 Lexington Avenue

100 Federal Street

Atlantic Wharf Office Building

343 Madison Avenue (2)

300 Binney Street (3)

290 Binney Street (4)

(1) The decrease was primarily attributable to a decrease in lease revenue from our clients.

(2) On August 27, 2025, we acquired our partner’s 45% ownership interest (See Note 10 to the Consolidated Financial Statements).

(3) Property was fully placed in-service on October 31, 2024.

(4) Property is currently in development.

Noncontrolling Interest—Common Units of the Operating Partnership

For BXP, noncontrolling interest—common units of the Operating Partnership increased by approximately $29.6 million for the year ended December 31, 2025 compared to 2024 due to an increase in allocable income, which was the result of recognizing greater gains on sales of real estate during 2025. Due to our ownership structure, there is no corresponding line item on BPLP’s financial statements.

Liquidity and Capital Resources

General

Our principal liquidity needs for the next twelve months and beyond are to:

• fund normal recurring expenses;

• meet debt service and principal repayment obligations on maturing debt, including:

• $100.0 million of principal outstanding on the 2024 Unsecured Term Loan due September 26, 2026, for which we have two, one-year extension options, subject to customary conditions;

• $1.0 billion of 2.750% unsecured senior notes due October 1, 2026; and

• amounts that become due under the Commercial Paper Program;

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• fund capital calls from our unconsolidated joint venture investments to fund development costs, capital improvements, leasing costs and debt principal repayment;

• fund mezzanine debt obligations;

• fund development and redevelopment costs;

• fund capital expenditures, including major renovations, tenant improvements and leasing costs;

• fund possible acquisitions of properties, either directly or indirectly through the acquisition of equity interests; and

• make the minimum distribution required to enable BXP to maintain its REIT qualification under the Code.

We expect to satisfy these needs using one or more of the following:

• cash flow from operations;

• distributions of cash flows from joint ventures;

• cash and cash equivalent balances;

• borrowings under BPLP’s Revolving Facility, unsecured term loans, short-term bridge facilities and construction loans (which may require guarantees by BPLP);

• proceeds from the sales of real estate and interests in joint ventures owning real estate, including proceeds generated from BXP’s asset sales program;

• long-term secured and unsecured indebtedness (including unsecured exchangeable indebtedness);

• private equity sources, including institutional investors;

• third-party fees generated by our property management, leasing, development and construction businesses; and

• issuances of BXP equity securities and/or preferred or common units of partnership interests in BPLP.

We draw on multiple financing sources to fund our long-term capital needs. We use BPLP’s 2025 Credit Facility primarily as a bridge facility to fund acquisition opportunities, refinance outstanding indebtedness, fund short-term development costs and for working capital. We also use BPLP’s 2025 Credit Facility to backstop the Commercial Paper Program. Although we may seek to fund our development projects with construction loans, which may require guarantees by BPLP, the source of financing for each particular project ultimately depends on several factors, including, among others, the project’s size and duration, whether the project is funded and owned by a joint venture, the extent of pre-leasing, our available cash and access to cost effective capital at the given time.

We seek to maximize income from our existing properties by maintaining quality standards for our properties that promote high occupancy rates and permit increases in rental rates while reducing client turnover and controlling operating expenses. Our sources of revenue also include third-party fees generated by our property management, leasing, development and construction businesses, interest earned on cash deposits and, from time to time, the sale of assets. We believe these capital sources will continue to meet our short-term liquidity needs. A material adverse change in one or more sources of capital may adversely affect our net cash flows and our ability to repay or refinance existing indebtedness as it matures.

Balance Sheet & Financing Activity

After the repayment at maturity of BPLP’s $1.0 billion unsecured senior notes due on February 1, 2026, as of February 20, 2026, we had available cash of approximately $363.4 million (of which approximately $93.0 million was attributable to our consolidated joint venture partners). Our liquidity and capital resources depend on a wide range of factors, and we believe that our access to capital and our strong liquidity, including the approximately $1.5 billion available under BPLP’s Revolving Facility (after deducting the $750.0 million being used as a backstop for the Commercial Paper Program) as of February 20, 2026, and our available cash are sufficient to fund our near term capital needs on existing development and redevelopment projects, repay our maturing indebtedness when due (if not refinanced or extended), satisfy our REIT distribution requirements (see “ REIT Tax Distribution Considerations ” below) and still allow us to act opportunistically on attractive investment opportunities.

From January 1, 2025 through February 20, 2026, we completed 14 sales transactions of which our share of the aggregate gross sales price was approximately $1.17 billion. Our share of the net proceeds from the sales from January 1, 2025 through December 31, 2025 was approximately $852.7 million.

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We may seek to enhance our liquidity to fund our current and future development activity, pursue additional attractive investment opportunities and refinance or repay indebtedness. Depending on then-current interest rates, the overall conditions in the public and private debt and equity markets, and our existing and expected leverage at the time, we may decide to access one or more of these capital sources. Doing so may result in greater cash and cash equivalents pending our use of the proceeds.

We have not sold any shares under BXP’s $600.0 million “at the market” equity offering program.

Construction & Redevelopment Activities

As of December 31, 2025, we have eight properties under development or redevelopment. Our share of the estimated total investment for these projects is approximately $3.9 billion, of which approximately $2.5 billion remained to be invested as of December 31, 2025. The commercial space in the pipeline, which excludes 651 Gateway and residential units, was approximately 61% pre-leased as of February 20, 2026.

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The following table presents information on properties under construction/redevelopment as of December 31, 2025 (dollars in thousands):

Financings

Construction/Redevelopment Properties

Estimated Stabilization Date

Location

# of Buildings

Estimated Square Feet

Investment to Date (1)(2)(3)

Estimated Total Investment (1)(2)

Total Available (1)

Outstanding at December 31, 2025

Estimated Future Equity Requirement (1)(2)(4)

Percentage Leased (5)

Office

725 12th Street (Redevelopment)

Washington, DC

343 Madison Avenue

New York, NY

Total Office Properties under Construction/Redevelopment

Laboratory/Life Sciences

290 Binney Street (55% ownership)

Cambridge, MA

651 Gateway (50% ownership) (Redevelopment)

South San Francisco, CA

Total Laboratory/Life Sciences Properties under Construction/Redevelopment

Residential

17 Hartwell Avenue (312 units) (20% ownership)

Lexington, MA

17 Hartwell Avenue - Retail

121 Broadway Street (439 units)

Cambridge, MA

290 Coles Street (670 Units) (19.46% ownership)

Jersey City, NJ

290 Coles Street - Retail

Total Residential Properties under Construction

Retail

Reston Next Retail

Reston, VA

Total Retail Properties under Construction

Total Properties under Construction/Redevelopment

(1) Represents our share.

(2) Each of Investment to Date, Estimated Total Investment and Estimated Future Equity Requirement represent our share of acquisition expenses, as applicable, and reflect our share of the estimated net revenue/expenses that we expect to incur prior to stabilization of the project, including any amounts actually received or paid through December 31, 2025.

(3) Includes approximately $124.3 million of unpaid but accrued construction costs and leasing commissions.

(4) Excludes approximately $124.3 million of unpaid but accrued construction costs and leasing commissions.

(5) Represents percentage leased as of February 20, 2026, including leases with future commencement dates. Percentage leased excludes 651 Gateway which was sold on January 2, 2026.

(6) The Estimated Total Investment reflects our 55% share of joint venture costs related to 290 Binney Street.  In addition, we have the sole obligation to construct an underground electrical vault for an estimated gross cost of $183.9 million. We have entered into a contract to sell the electrical vault to a third-party for a fixed price of $84.1 million upon completion.  The net investment of $99.8 million will be included in our outside basis in 290 Binney Street. We have invested $125.0 million for the vault as of December 31, 2025.

(7) On January 1, 2025, in accordance with our accounting policy, we ceased interest capitalization of our equity method investment. As of December 31, 2025, the joint venture partner, which is also the managing partner, classifies the project as under construction. As such, we continue to reflect the project as under construction. As of December 31, 2025, this development project was 27% placed in-service. On January 2, 2026, we sold our interest in the joint venture that owns Gateway Commons (See Note 17 to the Consolidated Financial Statements).

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(8) On March 5, 2025, we acquired a 19.46% interest in 290 Coles Street. The budget represents our 19.46% ownership of the project budget and financings which includes our share of preferred equity. We contributed $20.0 million of common equity at closing. In addition, we committed to provide up to $65.0 million in preferred equity accruing at a 13.0% IRR. As of December 31, 2025, approximately $29.9 million of preferred equity has been contributed.

(9) On January 16, 2026, this project was fully placed in-service.

(10) Percentage leased excludes 651 Gateway and the residential units.

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Inflation

We are exposed to inflation risk, as income from long-term leases is the primary source of our cash flows from operations. There are provisions in the majority of our client leases that protect us from, and mitigate the near term risk of, the impact of inflation. These provisions include rent steps and resets to market, reimbursement billings for operating expense pass-through charges, real estate tax and insurance reimbursements on a per-square-foot basis, or in some cases, annual reimbursement of operating expenses above a certain per-square-foot allowance. However, due to the long-term nature of the leases, the rent may not increase frequently enough to fully cover inflation.

REIT Tax Distribution Considerations

Dividend

As a REIT, BXP is subject to a number of organizational and operational requirements, including a requirement that BXP currently distribute at least 90% of its annual taxable income (excluding capital gains and with certain other adjustments). Our policy is for BXP to distribute at least 100% of its taxable income, including capital gains, to avoid paying federal tax. BXP’s Board of Directors will continue to evaluate BXP’s dividend rate in light of our actual and projected taxable income (including gains on sales), liquidity requirements and other circumstances, and there can be no assurance that the future dividends declared by BXP’s Board of Directors will not differ materially from the current quarterly dividend amount.

Holders of common and LTIP units (other than unearned MYLTIP units) of limited partnership interest in BPLP receive the same distribution per unit that is paid per share of BXP common stock.

Sales

To the extent that we sell assets at a gain and cannot efficiently use the proceeds in a tax deferred manner for either our development activities or acquisitions, BXP would, at the appropriate time, decide whether it is better to declare a special dividend, adopt a stock repurchase program, reduce indebtedness or retain the cash for future investment opportunities. Such a decision will depend on many factors including, among others, the timing, availability and terms of development and acquisition opportunities, our then-current and anticipated leverage, the cost and availability of capital from other sources, the price of BXP’s common stock and REIT distribution requirements. At a minimum, we expect that BXP would distribute at least that amount of proceeds necessary for BXP to avoid paying corporate level tax on the applicable gains realized from any asset sales.

From time to time in select cases, whether due to a change in use, structuring issues to comply with applicable REIT regulations or other reasons, we may sell an asset that is held by a taxable REIT subsidiary (“TRS”). Such a sale by a TRS would be subject to federal and local taxes.

Cash Flow Summary

The following summary discussion of our cash flows is based on the Consolidated Statements of Cash Flows and is not meant to be an all-inclusive discussion of the changes in our cash flows for the periods presented below.

Cash and cash equivalents and cash held in escrows aggregated approximately $1.6 billion and $1.3 billion at December 31, 2025 and 2024, respectively, representing an increase of approximately $222.1 million. The following table sets forth changes in cash flows:

Year ended December 31,

Change

(in thousands)

Net cash provided by operating activities

Net cash used in investing activities

Net cash used in financing activities

Our principal source of cash flow is related to the operation of our properties. The weighted-average term of our in-place leases, including leases signed by our unconsolidated joint ventures, excluding residential units, was approximately 7.9 years as of December 31, 2025, with occupancy rates historically in the range of approximately 86% to 92%. Generally, our properties generate a relatively consistent stream of cash flows that provides us with

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resources to pay operating expenses, debt service and fund regular quarterly dividend and distribution payment requirements. In addition, over the past several years, we have raised capital through the sale of some of our properties and through secured and unsecured borrowings.

Cash is used in investing activities to fund acquisitions, development, net investments in unconsolidated joint ventures and maintenance and repositioning capital expenditures. Cash is provided by investing activities from sales of real estate and net proceeds from notes receivables. Cash used in investing activities for the year ended December 31, 2025 and December 31, 2024 is detailed below:

Year ended December 31,

(in thousands)

Acquisitions of real estate (1)

Construction in progress (2)

Building, pre-development and other capital improvements (3)

Tenant improvements

Proceeds from sales of real estate (4)

Acquisition of real estate upon consolidation of unconsolidated joint ventures (net of cash) (5)

Capital contributions to unconsolidated joint ventures (6)

Capital distributions from unconsolidated joint ventures (7)

Investment in non-real estate investments

Issuance of note receivables (including related party) (8)

Proceeds from note receivables (including related party) (8)

Investments in securities, net

Net cash used in investing activities

Cash used in investing activities changed primarily due to the following:

(1) On December 15, 2025, we completed the acquisition of 2100 M Street, located in Washington, D.C., for a purchase price, including transaction costs, of approximately $55.9 million. The acquisition was completed with available cash. We intend to redevelop 2100 M Street in the future.

On December 27, 2024, we completed the acquisition of 725 12th Street located in Washington, DC, for a             purchase price, including transaction costs, of approximately $35.4 million. The acquisition was completed with available cash. Following the acquisition, we commenced redevelopment of the property.

(2) Construction in progress for the year ended December 31, 2025 included ongoing expenditures associated with Reston Next Office Phase II, Reston Next Retail and 1050 Winter Street, which were partially or fully placed in-service during the year ended December 31, 2025. In addition, we incurred costs associated with our continued development/redevelopment of 290 Binney Street, 121 Broadway, 725 12th Street and 343 Madison Avenue.

Construction in progress for the year ended December 31, 2024 included ongoing expenditures associated with 760 Boylston Street, 180 CityPoint, 103 CityPoint and 300 Binney Street, which were fully placed in-service during the year ended December 31, 2024. In addition, we incurred costs associated with our continued development/redevelopment of Reston Next Office Phase II that was partially placed in-service, 290 Binney Street, 121 Broadway and 725 12th Street.

(3) Building, pre-development and other capital improvements for the year ended December 31, 2025 and December 31, 2024 included approximately $39.4 million and $47.9 million, respectively, of pre-development expenditures associated with the 343 Madison Avenue project. Beginning July 31, 2025, costs associated with the continued development of 343 Madison Avenue are included within construction in progress.

(4) Proceeds from sales of real estate for the year ended December 31, 2025 consisted of eight transactions (See Note 3 to the Consolidated Financial Statements).

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(5) On January 8, 2024, we completed the acquisition of our joint venture partner’s 50% economic ownership interest in the joint venture that owns 901 New York Avenue, located in Washington, DC, for a gross purchase price of $10.0 million and we acquired net working capital, including cash and cash equivalents of approximately $16.1 million.

(6) Capital contributions to unconsolidated joint ventures for the year ended December 31, 2025 consisted primarily of cash contributions of approximately $102.7 million, $49.9 million, $42.0 million, $21.2 million and $14.8 million to our Dock 72, 290 Coles Street, 360 Park Avenue South, 751 Gateway, and 200 Fifth Avenue joint ventures, respectively. On March 5, 2025, we entered into a new joint venture for the development of 290 Coles Street (See Note 5 to the Consolidated Financial Statements).

Capital contributions to unconsolidated joint ventures for the year ended December 31, 2024 consisted primarily of cash contributions of approximately $62.7 million, $32.1 million, $13.5 million and $11.6 million to our 360 Park Avenue South, Gateway Commons, Platform 16 and Dock 72 joint ventures, respectively.

(7) Capital distributions from unconsolidated joint ventures for the year ended December 31, 2025 consisted of cash distributions totaling approximately $143.5 million and $29.2 million from our 751 Gateway and Beach Cities Media Campus joint ventures, respectively, resulting from excess proceeds from each of the sales.

Capital distributions from unconsolidated joint ventures for the year ended December 31, 2024 consisted primarily of cash distributions from our 360 Park Avenue South joint venture.

(8) On October 17, 2025, our 3 Hudson Boulevard joint venture refinanced its debt and proceeds from the new loans were used to repay the existing $80.0 million related party note receivable. Funding for the mezzanine loan, which has a maximum commitment of $50.0 million, totaled approximately $18.4 million for the year ended December 31, 2025 (See Note 6 to the Consolidated Financial Statements).

Cash used in financing activities for the year ended December 31, 2025 totaled approximately $378.6 million. This amount consisted primarily of the repayment of BPLP’s $850.0 million in aggregate principal amount of its 3.200% unsecured senior notes due January 15, 2025 and the payment of our regular dividends and distributions to our shareholders and unitholders, partially offset by the net proceeds from the issuance of BPLP’s $1.0 billion in aggregate principal amount of its 2.00% unsecured exchangeable senior notes. The unsecured exchangeable senior notes are due October 2030 and net proceeds, including the purchase of the capped call transactions entered into simultaneously with the exchangeable senior notes closing, totaled approximately $940.1 million. Future debt payments are discussed below under the heading “Debt. ”

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Capitalization

The following table presents Consolidated Market Capitalization and BXP’s Share of Market Capitalization, as well as the corresponding ratios of Consolidated Debt to Consolidated Market Capitalization and BXP’s Share of Debt to BXP’s Share of Market Capitalization (in thousands, except for percentages):

December 31, 2025

Shares / Units Outstanding

Common Stock Equivalent

Equivalent Value (1)

Common Stock

Common Operating Partnership Units

Total Equity

Consolidated Debt

Add:

BXP’s share of unconsolidated joint venture debt (3)

Subtract:

Partners’ share of Consolidated Debt (4)

BXP’s Share of Debt

Consolidated Market Capitalization

BXP’s Share of Market Capitalization

Consolidated Debt/Consolidated Market Capitalization

BXP’s Share of Debt/BXP’s Share of Market Capitalization

(1) Values are based on the closing price per share of BXP’s common stock on the New York Stock Exchange on December 31, 2025 of $67.48.

(2) Includes long-term incentive plan units (including 2012 OPP Units and 2013 - 2022 MYLTIP Units but excludes the 2023 - 2025 MYLTIP Units and 2025 OPP Units because the performance periods had not ended as of December 31, 2025).

(3) See page 85 for additional information.

(4) See page 83 for additional information.

Consolidated Debt to Consolidated Market Capitalization Ratio is a measure of leverage commonly used by analysts in the REIT sector. We present this measure as a percentage and it is calculated by dividing (A) our consolidated debt by (B) our consolidated market capitalization, which is the market value of our outstanding equity securities plus our consolidated debt. Consolidated market capitalization is the sum of:

(1)     our consolidated debt; plus

(2)     the product of (x) the closing price per share of BXP common stock on December 31, 2025, as reported by the New York Stock Exchange, multiplied by (y) the sum of:

(i)     the number of outstanding shares of common stock of BXP,

(ii)     the number of outstanding OP Units in BPLP (excluding OP Units held by BXP),

(iii)     the number of OP Units issuable upon conversion of all outstanding LTIP Units, assuming all conditions have been met for the conversion of the LTIP Units, and

(iv)     the number of OP Units issuable upon conversion of 2012 OPP Units, and 2013 - 2022 MYLTIP Units that were issued in the form of LTIP Units.

The calculation of consolidated market capitalization does not include LTIP Units issued in the form of Outperformance Awards or MYLTIP Awards unless and until certain performance thresholds are achieved and they are earned. Because their performance periods have not yet ended, the 2023 - 2025 MYLTIP Units and 2025 OPP Units are not included in this calculation as of December 31, 2025.

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We also present BXP’s Share of Market Capitalization and BXP’s Share of Debt/BXP’s Share of Market Capitalization, which are calculated in the same manner, except that BXP’s Share of Debt is utilized instead of our consolidated debt in both the numerator and the denominator. BXP’s Share of Debt is defined as our consolidated debt plus our share of debt from our unconsolidated joint ventures (calculated based upon our ownership percentage), minus our partners’ share of debt from our consolidated joint ventures (calculated based upon the partners’ percentage ownership interests adjusted for basis differentials). Management believes that BXP’s Share of Debt provides useful information to investors regarding our financial condition because it includes our share of debt from unconsolidated joint ventures and excludes our partners’ share of debt from consolidated joint ventures, in each case presented on the same basis. We have several significant joint ventures and presenting various measures of financial condition in this manner can help investors better understand our financial condition and/or results of operations after taking into account our economic interest in these joint ventures.  We caution investors that the ownership percentages used in calculating BXP’s Share of Debt may not completely and accurately depict all of the legal and economic implications of holding an interest in a consolidated or unconsolidated joint venture. For example, in addition to partners’ interests in profits and capital, venture agreements vary in the allocation of rights regarding decision making (both for routine and major decisions), distributions, transferability of interests, financing and guarantees, liquidations and other matters.  Moreover, in some cases we exercise significant influence over, but do not control, the joint venture in which case GAAP requires that we account for the joint venture entity using the equity method of accounting and we do not consolidate it for financial reporting purposes. In other cases, GAAP requires that we consolidate the venture even though our partner(s) own(s) a significant percentage interest.  As a result, management believes that the presentation of BXP’s Share of a financial measure should not be considered a substitute for, and should only be considered with and as a supplement to our financial information presented in accordance with GAAP.

We present these supplemental ratios because our degree of leverage could affect our ability to obtain additional financing for working capital, capital expenditures, acquisitions, development or other general corporate purposes and because different investors and lenders consider one or both of these ratios. Investors should understand that these ratios are, in part, a function of the market price of the common stock of BXP and as such will fluctuate with changes in such price, and they do not necessarily reflect our capacity to incur additional debt to finance our activities or our ability to manage our existing debt obligations. However, for a company like BXP, whose assets are primarily income-producing real estate, these ratios may provide investors with an alternate indication of leverage, so long as they are evaluated along with the ratio of indebtedness to other measures of asset value used by financial analysts and other financial ratios, as well as the various components of our outstanding indebtedness.

For a discussion of our unconsolidated joint venture indebtedness, see “ Liquidity and Capital Resources—Investment in Unconsolidated Joint Ventures - Secured Debt” w ithin “ Item 7—Management’s Discussion and Analysis of Financial Condition and Results of Operations ” and for a discussion of our consolidated joint venture indebtedness see “Debt ” below.

Debt

For further discussion on the terms of our debt, see Note 7 to the Consolidated Financial Statements. The following table summarizes certain information with respect to our indebtedness outstanding as of December 31, 2025 and 2024 (dollars in thousands).

Interest Rate

Amount

Stated

GAAP (1)

Maturity Date

Unsecured Senior Notes (2)

Unsecured Senior Notes (3)

January 15, 2025

Unsecured Senior Notes (4)

February 1, 2026

Unsecured Senior Notes

October 1, 2026

Unsecured Senior Notes

December 1, 2027

Unsecured Senior Notes

December 1, 2028

Unsecured Senior Notes

June 21, 2029

Unsecured Senior Notes

March 15, 2030

Unsecured Senior Notes

January 30, 2031

Unsecured Senior Notes

April 1, 2032

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Interest Rate

Amount

Stated

GAAP (1)

Maturity Date

Unsecured Senior Notes

October 1, 2033

Unsecured Senior Notes

January 15, 2034

Unsecured Senior Notes

January 15, 2035

Total Principal Amount

Less: Unamortized discount and deferred financing costs, net

Carrying Amount

Unsecured Exchangeable Senior Notes

October 1, 2030

Less: Unamortized deferred financing costs

Carrying Amount

Unsecured Commercial Paper (5)

Various

Unsecured Line of Credit (Revolving Credit Facility) (6)

March 29, 2030

Unsecured Term Loans

2023 Unsecured Term Loan

2024 Unsecured Term Loan (7)

September 26, 2026

Unsecured Term Loan Facility (8)

March 30, 2029

Total Principal Amount

Less: Deferred financing costs and fair value adjustments, net

Carrying Amount

Mortgage Notes

767 Fifth Avenue (the General Motors Building) (60% ownership) (2)(9)

June 9, 2027

Santa Monica Business Park (2)(10)

October 8, 2028

90 Broadway, 325 Main Street, 355 Main Street, and Cambridge East Garage (also known as Kendall Center Green Garage) (2)(11)

October 26, 2028

901 New York Avenue (12)

January 5, 2029

601 Lexington Avenue (55% ownership) (2)

January 9, 2032

Total Principal Amount

Less: Deferred financing costs and fair value adjustments, net

Carrying Amount

Total Consolidated Debt

(1) For the unsecured senior notes, the GAAP rate represents the yield on issuance date including the effects of discounts on the notes, settlements of interest rate contracts and the amortization of financing costs. For all other debt, the GAAP interest rate differs from the stated interest rate due to the inclusion of the amortization of financing charges, the effects of hedging transactions (if any and excluding capped calls classified as equity) and adjustments required under ASC 805 “Business Combinations” to reflect loans and swaps at their fair values (if any).

(2) No principal amounts are due prior to maturity.

(3) This unsecured senior note was repaid at maturity, see Note 7 to the Consolidated Financial Statements.

(4) See Note 17 to the Consolidated Financial Statements.

(5) At December 31, 2025, the weighted average interest rate of the commercial paper notes outstanding was approximately 3.99% per annum and had a weighted-average maturity of 45 days from the date of issuance. At

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February 20, 2026, BPLP had an aggregate of $750.0 million of commercial paper notes outstanding that bore interest at a weighted-average rate of approximately 3.93% per annum and had a weighted-average maturity of 44 days, from the date of issuance.

(6) The unsecured line of credit bears interest at a variable rate of SOFR+0.85% per annum. The 2025 Credit Facility is used as a backstop for the $750.0 million Commercial Paper Program. As such, BPLP intends to maintain, at a minimum, availability under the unsecured line of credit in an amount equal to the amount of unsecured commercial paper notes outstanding. The table below provides the principal indebtedness outstanding and remaining capacity under the unsecured line of credit at December 31, 2025 and February 20, 2026 (dollars in thousands).

December 31, 2025

February 20, 2026

Facility

Outstanding

Remaining Capacity

Outstanding

Remaining Capacity

Unsecured Line of Credit

Less:

Unsecured Commercial Paper

Letters of Credit

Total Remaining Capacity

(7) The 2024 Unsecured Term Loan bears interest at a variable rate of SOFR+1.05% per annum. BPLP entered into an interest rate swap contract to fix SOFR at a weighted-average fixed interest rate of 3.6775% per annum for the period commencing on April 7, 2025 and ending on April 6, 2026. Stated interest rate reflects the weighted-average fixed interest rate based on the interest rate swap contracts plus 1.05% per annum. The 2024 Unsecured Term Loan has two one-year extension options, subject to certain conditions.

(8) The Unsecured Term Loan Facility bears interest at a variable rate of SOFR+0.95% per annum and has two six-month extension options, each subject to customary conditions.

(9) In connection with the refinancing of the loan, we guaranteed the consolidated entity’s obligation to fund various reserves for tenant improvement costs and allowances, leasing commissions and free rent obligations in lieu of cash deposits. As of December 31, 2025, the maximum funding obligation under the guarantee was approximately $6.4 million. We earn a fee from the joint venture for providing the guarantee and have an agreement with our partners to reimburse the joint venture for their share of any payments made under the guarantee.

(10) The mortgage loan bears interest at a variable rate of Daily Simple SOFR+1.60% per annum. BPLP entered into an interest rate swap contract to fix Daily Simple SOFR at a weighted-average fixed interest rate of 3.6775% per annum for the period commencing on April 7, 2025 and ending on April 6, 2026. Stated interest rate reflects the weighted-average fixed interest rate based on the interest rate swap contracts plus 1.60% per annum.

(11) The mortgage loan bears interest at a variable rate of Daily Compounded SOFR+2.25% per annum. BPLP entered into three interest rate swap contracts with notional amounts aggregating $600.0 million to fix Daily Compounded SOFR at a weighted-average fixed interest rate of 3.7925% for the period commencing on December 15, 2023 and ending on October 26, 2028. The stated interest rate reflects the weighted average fixed interest rate based on the interest rate swap contracts plus 2.25% per annum.

(12) The loan has a one-year extension option remaining, subject to certain conditions.

The following table lists our mortgage notes, net outstanding and our partners’ share, based on their respective ownership percentage, from our consolidated joint ventures as of December 31, 2025 (dollars in thousands).

Carrying Amount

Properties

Partners ’ Share

Wholly-owned

901 New York Avenue

Santa Monica Business Park

90 Broadway, 325 Main Street, 355 Main Street, and Cambridge East Garage (also known as Kendall Center Green Garage)

Subtotal

Consolidated Joint Ventures

767 Fifth Avenue (the General Motors Building) (60% ownership) (1)

601 Lexington Avenue (55% ownership)

Subtotal

Total

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(1) The partners’ share of the carrying amount has been adjusted for basis differentials.

The following table lists the contractual aggregate principal payments of mortgage notes payable at December 31, 2025:

Principal Payments

Year

(in thousands)

Thereafter

The table below provides the debt statistics of our outstanding consolidated indebtedness at December 31, 2025 and December 31, 2024.

December 31, 2025

December 31, 2024

Weighted Average

Weighted Average

% of Total Debt

Stated Rates

GAAP Rates (1)

Maturity (years)

% of Total Debt

Stated Rates

GAAP Rates (1)

Maturity (years)

Floating Rate Debt (2)

Fixed Rate Debt (3)

Consolidated Debt

Unsecured Debt

Secured Debt

Consolidated Debt

(1) The GAAP interest rate differs from the stated interest rate due to the inclusion of the amortization of financing charges, the effects of hedging transactions (if any and excluding capped calls classified as equity) and adjustments required under ASC 805 “Business Combinations” to reflect loans and swaps at their fair values (if any).

(2) The unsecured commercial paper notes are included in our floating rate debt statistics. At December 31, 2025, the weighted average interest rate of the unsecured commercial paper notes outstanding was approximately 3.99% per annum and had a weighted-average maturity of 45 days from the date of issuance.

(3) The Fixed Rate Debt includes the effects of hedging transactions.

Derivative Instruments and Hedging Activities

As of December 31, 2025, we had $900.0 million of interest rate swaps outstanding, where hedge accounting was elected, with a fair value of approximately $(8.3) million. On April 8, 2025, we entered into an interest rate swap contract with a notional amount of $300.0 million to replace $300.0 million of interest rate swaps that expired on April 1, 2025. For a description of these interest rate swaps, see Note 8 to the Consolidated Financial Statements.

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Investment in Unconsolidated Joint Ventures - Secured Debt

We have investments in unconsolidated joint ventures with our effective ownership interests ranging from approximately 19% to approximately 71%. Fourteen of these ventures have mortgage indebtedness. We exercise significant influence over, but do not control, these entities. As a result, we account for them using the equity method of accounting. See also Note 6 to the Consolidated Financial Statements. At December 31, 2025, the aggregate carrying amount of debt, including both our and our partners’ share, incurred by these ventures was approximately $2.9 billion (of which our proportionate share is approximately $1.2 billion). The table below summarizes the outstanding debt of these joint venture properties at December 31, 2025. In addition to other guarantees specifically noted in the table, we have agreed to customary environmental indemnifications and nonrecourse carve-outs (e.g., guarantees against fraud, misrepresentation and bankruptcy) as well as the completion of development projects on certain of the loans.

Properties

Nominal % Ownership

Stated Interest Rate

GAAP Interest Rate (1)

Term of Variable Rate + Spread

Stated Principal Amount

Deferred Financing Costs, Net

Carrying Amount

Carrying Amount (Our share)

Maturity Date

(dollars in thousands)

360 Park Avenue South

Term SOFR+2.50%

December 13, 2027

1265 Main Street

January 1, 2032

Colorado Center

August 9, 2027

The Hub on Causeway - Podium & 100 Causeway Street

April 9, 2031

Hub50House

SOFR+1.35%

June 17, 2032

7750 Wisconsin Avenue (Marriott International Headquarters)

February 27, 2035

Safeco Plaza

SOFR+2.32%

September 1, 2026

500 North Capitol Street, NW

June 5, 2026

200 Fifth Avenue

Term SOFR+1.41%

November 24, 2028

3 Hudson Boulevard

Term SOFR+5.25%

November 7, 2027

3 Hudson Boulevard

Term SOFR+7.25%

November 7, 2027

Skymark - Reston Next Residential

SOFR+2.00%

May 13, 2026

17 Hartwell Avenue

July 10, 2030

290 Coles Street

Term SOFR+2.50%

March 5, 2029

Total

(1) The GAAP interest rate differs from the stated interest rate due to the inclusion of the amortization of financing costs, which includes mortgage recording fees, the effects of hedging transactions (if any) and adjustments required under ASC 805 “Business Combinations” to reflect loans at their fair values (if any).

(2) The loan requires interest only payments with a balloon payment due at maturity.

(3) The loan includes certain extension options, subject to certain conditions.

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(4) The joint venture entered into an interest rate cap agreement with a financial institution to limit its exposure to increases in Term SOFR rate to a cap of 5.00% per annum on a notional amount of $220.0 million through January 15, 2026. On January 6, 2026, the joint venture entered into a new interest rate cap agreement that continued to cap Term SOFR rate at 5.00% per annum on a notional amount of $220.0 million through January 15, 2027.

(5) The joint venture entered into interest rate swap contracts with notional amounts aggregating $185.0 million through April 10, 2032, resulting in a fixed rate of approximately 4.432% per annum through the expiration of the interest rate swap contracts.

(6) The loan bears interest at a variable rate equal to the greater of (x) 2.35% or (y) SOFR plus 2.32% per annum. The joint venture entered into an interest rate cap agreement with a financial institution to limit its exposure to increases in the SOFR rate at a cap of 2.50% per annum on a notional amount of $250.0 million through September 1, 2026.

(7) The indebtedness consists of (x) a $70.0 million mortgage loan payable (Note A) which bears interest at a fixed rate of 6.23% per annum, and (y) a $35.0 million mortgage loan payable (Note B) which bears interest at a fixed rate of 8.03% per annum. We provided $10.5 million of the Note B mortgage financing to the joint venture. Our portion of the loan is reflected as Related Party Notes Receivable, Net on our Consolidated Balance Sheets.

(8) The joint venture entered into interest rate swap contracts with notional amounts aggregating $600.0 million through June 2028, resulting in a fixed rate of approximately 4.34% per annum through the expiration of the interest rate swap contracts.

(9) The indebtedness consists of (x) a $108.0 million senior loan with a third-party lender and (y) a mezzanine loan provided by us with a maximum commitment of $50.0 million. As of December 31, 2025, we have funded approximately $18.4 million of the mezzanine loan. The loan is reflected as Related Party Note Receivables, Net on our Consolidated Balance Sheets.

(10) The joint venture entered into an interest rate cap agreement with a financial institution to limit its exposure to increases in Term SOFR rate to a cap of 6.00% per annum on a notional amount of $108.0 million through November 9, 2027.

(11) The construction financing has a borrowing capacity of $140.0 million.

(12) No amounts have been drawn under the $98.7 million construction loan.

(13) No amounts have been drawn under the $225.0 million construction loan.

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Funds from Operations

Pursuant to the revised definition of FFO adopted by the Board of Governors of the National Association of Real Estate Investment Trusts (“Nareit”), we calculate FFO for each of BXP and BPLP by adjusting net income attributable to BXP, Inc. and net income attributable to Boston Properties Limited Partnership (computed in accordance with GAAP), respectively, for gains (or losses) from sales of properties, including a change in control, impairment losses on depreciable real estate consolidated on our balance sheet, impairment losses on our investments in unconsolidated joint ventures driven by a measurable decrease in the fair value of depreciable real estate held by the unconsolidated joint ventures and our share of real estate-related depreciation and amortization. FFO is a non-GAAP financial measure. We believe the presentation of FFO, combined with the presentation of required GAAP financial measures, improves the understanding of operating results of REITs among the investing public and helps make comparisons of REIT operating results more meaningful. Management generally considers FFO to be a useful measure for understanding and comparing our operating results because, by excluding gains and losses related to sales or a change in control of previously depreciated operating real estate assets, impairment losses and real estate asset depreciation and amortization (which can differ across owners of similar assets in similar condition based on historical cost accounting and useful life estimates), FFO can help investors compare the operating performance of a company’s real estate across reporting periods and to the operating performance of other companies.

Our computation of FFO may not be comparable to FFO reported by other REITs or real estate companies that do not define the term in accordance with the current Nareit definition or that interpret the current Nareit definition differently. We believe that in order to facilitate a clear understanding of our operating results, FFO should be examined in conjunction with net income attributable to BXP, Inc. and net income attributable to Boston Properties Limited Partnership as presented in our Consolidated Financial Statements. FFO should not be considered as a substitute for net income attributable to BXP, Inc. or net income attributable to Boston Properties Limited Partnership (determined in accordance with GAAP) or any other GAAP financial measures and should only be considered together with and as a supplement to our financial information prepared in accordance with GAAP.

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BXP

The following table presents a reconciliation of net income attributable to BXP, Inc. to FFO attributable to BXP, Inc. for the years ended December 31, 2025, 2024 and 2023:

Year ended December 31,

(in thousands)

Net income attributable to BXP, Inc.

Add:

Noncontrolling interest—common units of the Operating Partnership

Noncontrolling interests in property partnerships

Net income

Add:

Depreciation and amortization

Noncontrolling interests in property partnerships’ share of depreciation and amortization

BXP’s share of depreciation and amortization from unconsolidated joint ventures

Corporate-related depreciation and amortization

Non-real estate depreciation and amortization

Loss on sales-type lease

Impairment losses

Impairment losses included within loss from unconsolidated joint ventures

Less:

Gain on sale / consolidation included within loss from unconsolidated joint ventures

Gains on sales of real estate

Gain on sales-type lease included within loss from unconsolidated joint ventures

Unrealized gain (loss) on non-real estate investments

Noncontrolling interests in property partnerships

Funds from Operations (FFO) attributable to the Operating Partnership common unitholders (including BXP, Inc.)

Less:

Noncontrolling interest—common units of the Operating Partnership’s share of funds from operations

Funds from Operations attributable to BXP, Inc.

Our percentage share of Funds from Operations—basic

Weighted average shares outstanding—basic

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The following tables presents a reconciliation of net income attributable to BXP, Inc. to Diluted FFO attributable to BXP, Inc. for income (numerator) and shares/units (denominator) for the years ended December 31, 2025, 2024 and 2023:

Year ended December 31,

(in thousands)

Net income attributable to BXP, Inc.

Add:

Noncontrolling interest—common units of the Operating Partnership

Noncontrolling interests in property partnerships

Net income

Add:

Depreciation and amortization

Noncontrolling interests in property partnerships’ share of depreciation and amortization

BXP’s share of depreciation and amortization from unconsolidated joint ventures

Corporate-related depreciation and amortization

Non-real estate depreciation and amortization

Loss on sales-type lease

Impairment losses

Impairment losses included within loss from unconsolidated joint ventures

Less:

Gain on sale / consolidation included within loss from unconsolidated joint ventures

Gains on sales of real estate

Gain on sales-type lease included within loss from unconsolidated joint ventures

Unrealized gain (loss) on non-real estate investments

Noncontrolling interests in property partnerships

Funds from Operations (FFO) attributable to the Operating Partnership common unitholders (including BXP, Inc.)

Effect of Dilutive Securities:

Stock based compensation

Diluted FFO

Less:

Noncontrolling interest—common units of the Operating Partnership’s share of diluted FFO

Diluted FFO attributable to BXP, Inc. (1)

(1) BXP’s share of diluted Funds from Operations was 90.06%, 89.80% and 89.76% for the years ended December 31, 2025, 2024 and 2023, respectively.

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Year ended December 31,

shares/units (in thousands)

Basic Funds from Operations

Effect of Dilutive Securities:

Stock based compensation

Diluted Funds from Operations

Less:

Noncontrolling interest—common units of the Operating Partnership’s share of diluted Funds from Operations

Diluted Funds from Operations attributable to BXP, Inc. (1)

(1) BXP’s share of diluted Funds from Operations was 90.06%, 89.80% and 89.76% for the years ended December 31, 2025, 2024 and 2023, respectively.

BPLP

The following table presents a reconciliation of net income attributable to Boston Properties Limited Partnership to FFO attributable to Boston Properties Limited Partnership for the years ended December 31, 2025, 2024 and 2023:

Year ended December 31,

(in thousands)

Net income attributable to Boston Properties Limited Partnership

Add:

Noncontrolling interests in property partnerships

Net income

Add:

Depreciation and amortization

Noncontrolling interests in property partnerships’ share of depreciation and amortization

BXP’s share of depreciation and amortization from unconsolidated joint ventures

Corporate-related depreciation and amortization

Non-real estate depreciation and amortization

Loss on sales-type lease

Impairment losses

Impairment losses included within loss from unconsolidated joint ventures

Less:

Gain on sale / consolidation included within loss from unconsolidated joint ventures

Gains on sales of real estate

Gain on sales-type lease included within loss from unconsolidated joint ventures

Unrealized gain (loss) on non-real estate investments

Noncontrolling interests in property partnerships

Funds from Operations attributable to Boston Properties Limited Partnership (1)

Weighted average shares outstanding—basic

(1) Our calculation includes OP Units and vested LTIP Units (including vested 2012 OPP Units and vested 2013 - 2022 MYLTIP Units).

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The following table presents a reconciliation of net income attributable to Boston Properties Limited Partnership to Diluted FFO attributable to Boston Properties Limited Partnership for income (numerator) and shares/units (denominator) for the years ended December 31, 2025, 2024 and 2023:

Year ended December 31,

(in thousands)

Net income attributable to Boston Properties Limited Partnership

Add:

Noncontrolling interests in property partnerships

Net income

Add:

Depreciation and amortization

Noncontrolling interests in property partnerships’ share of depreciation and amortization

BXP’s share of depreciation and amortization from unconsolidated joint ventures

Corporate-related depreciation and amortization

Non-real estate depreciation and amortization

Loss on sales-type lease

Impairment losses

Impairment losses included within loss from unconsolidated joint ventures

Less:

Gain on sale / consolidation included within loss from unconsolidated joint ventures

Gains on sales of real estate

Gain on sales-type lease included within loss from unconsolidated joint ventures

Unrealized gain (loss) on non-real estate investments

Noncontrolling interests in property partnerships

Funds from Operations attributable to Boston Properties Limited Partnership (1)

Effect of Dilutive Securities:

Stock based compensation

Diluted Funds from Operations attributable to Boston Properties Limited Partnership

(1) Our calculation includes OP Units and vested LTIP Units (including vested 2012 OPP Units and vested 2013 - 2022 MYLTIP Units).

Year ended December 31,

shares/units (in thousands)

Basic Funds from Operations

Effect of Dilutive Securities:

Stock based compensation

Diluted Funds from Operations

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Material Cash Commitments

As of December 31, 2025, we were subject to contractual payment obligations, excluding our unconsolidated joint ventures commitments. For details about our unconsolidated joint venture contractual payment obligations see “ Investments in Unconsolidated Joint Ventures - Contractual Obligations” below. Our primary contractual payment obligations, that are not disclosed in other sections of this Annual Report on Form 10-K, are client and development related and described in further detail below. For details about our other contractual payment obligations related to operating and finance leases and debt, see Notes 4 and 7 to the Consolidated Financial Statements, respectively.

Payments Due by Period

Total

Thereafter

(in thousands)

Commitments:

Client obligations (1)

Construction contracts for development projects (2)

Total Commitments

(1) Committed client-related obligations (tenant improvements and lease commissions) based on executed leases as of December 31, 2025. The timing and amount of these payments is subject to change.

(2) Payments for construction contracts for development projects includes consolidated joint ventures and represents 100% of the estimated development costs.

We invest in two non-real estate funds, which are primarily environmentally focused investment funds, each with a commitment to contribute $10.0 million, aggregating to a total commitment of $20.0 million. As of December 31, 2025, we have contributed approximately $10.5 million, which includes required fees, with $9.5 million remaining to be contributed.

Investment in Unconsolidated Joint Ventures - Contractual Obligations

As of December 31, 2025, the unconsolidated joint ventures that we have an ownership interest in were subject to contractual payment obligations as described in the table below.  The table represents our share of the contractual obligations. For details about our unconsolidated joint ventures secured debt see “ Investment In Unconsolidated Joint Ventures - Secured Deb t ” referred to in “ Item 7—Management’s Discussion and Analysis of Financial Condition and Results of Operations—Liquidity and Capital Resources.”

Payments Due by Period

Total

Thereafter

(in thousands)

Contractual Obligations:

Operating leases (1)

Total Contractual Obligations

Commitments:

Client obligations (2)

Construction contracts for development projects

Total Commitments

(1) Operating leases include approximately $61.6 million related to renewal options that the joint venture is reasonably certain it will exercise.

(2) Committed client-related obligations (tenant improvements and lease commissions) based on executed leases as of December 31, 2025. The timing and amount of these payments is subject to change.

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We have various service contracts with vendors related to our property management. In addition, we have certain other contracts we enter into in the ordinary course of business that may extend beyond one year. These contracts include terms that provide for cancellation with insignificant or no cancellation penalties. Contract terms are generally between three and five years.

During the year ended December 31, 2025, we paid approximately $461.4 million to fund client-related obligations, including tenant improvements and leasing commissions.

In addition, during the year ended December 31, 2025, we and our unconsolidated joint venture partners incurred approximately $529.8 million of new tenant-related obligations associated with approximately 4.6 million square feet of second generation leases, or approximately $116 per square foot. In addition, we signed leases for approximately 1.0 million square feet of first generation leases.  The tenant-related obligations for the development properties are included within the projects’ “Estimated Total Investment” referred to in “ Item 7—Management’s Discussion and Analysis of Financial Condition and Results of Operations—Liquidity and Capital Resources.” In the aggregate, during 2025, we signed leases for approximately 5.6 million square feet of space and incurred aggregate tenant-related obligations of approximately $767.2 million, or approximately $138 per square foot.