CBU Community Bank System, Inc. - 8-K

Item 5.02               Departure of Directors or Certain
Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

(d)           On
February 11, 2026, Community Financial System, Inc.’s (the “Company”) Board of Directors (the “Board”) elected
Brenda M. Hall as a new independent director, effective as of March 1, 2026. Ms. Hall is the former Executive Vice President and Chief
Operating Officer of Standard Lines (“COO”) at Selective Insurance Group, Inc. (“Selective”), where she built
a distinguished 24-year career marked by progressive advancement and increasing leadership responsibilities.

During her tenure at Selective, Ms. Hall most recently served as Chief
Operating Officer from October 2019 until her retirement in January 2026. In this role, she oversaw the company’s largest business
segment, leading the development and execution of growth strategies, expansion into new geographic markets, enhancement of data-driven
operations, and integration of predictive modeling into underwriting processes. Prior to her role as COO, Ms. Hall held several senior
leadership positions at Selective, including Senior Vice President, Chief Strategic Operations Officer, and Senior Vice President, Director
of Field Underwriting.

The Board has determined that Ms. Hall qualifies
as an independent director under New York Stock Exchange and Board standards. With her appointment, the Board now consists of 14 directors,
13 of whom are independent. Ms. Hall has also joined the Board of Directors of Community Bank, N.A., the Company’s banking subsidiary,
and will serve on the Risk Committee of the Company and the Bank.

There are no arrangements or understandings with
any person regarding Ms. Hall’s selection as director. Ms. Hall has no related party transactions with the Company requiring disclosure
under Item 404(a) of Regulation S-K. She will receive compensation consistent with other non-employee directors, as described in the Company’s
Proxy Statement on Schedule 14A.

A copy of the press release announcing Ms. Hall’s
appointment is attached hereto as Exhibit 99.1 and is incorporated by reference into this Current Report on Form 8-K.

Item 9.01               Financial Statements and Exhibits

(d)  Exhibits

99.1

Press Release, dated February 11, 2026, issued by Community Financial System, Inc.

104

Cover Page Interactive Data File (embedded in the cover page formatted in Inline XBRL)