Form 4 Filing for Community Financial System, Inc.

This filing details a transaction by Singh Savneet, a director at Community Financial System, Inc. On September 9, 2026, Singh Savneet acquired 400 shares of Common Stock through a purchase transaction. The weighted average price for these shares was $62.47, with individual transactions ranging from $62.41 to $62.53. Following this acquisition, Singh Savneet now owns 418 shares of Common Stock directly. The filing also includes information about holdings in phantom stock units related to the Deferred Compensation Plan for Directors and the 2022 Long-Term Incentive Plan, which are economic equivalents of common stock and will be settled in shares at future dates. These phantom stock holdings include dividend equivalents acquired on April 10, 2026, and July 10, 2026.