Steven C. Finch - Form 3 Filing and Power of Attorney

This filing includes Form 3, which reports initial ownership of securities, and an accompanying Limited Power of Attorney. Steven C. Finch, a director at FINANCIAL INSTITUTIONS INC (FISI), has filed this document. The Form 3 indicates that Finch currently owns 0 shares of common stock. The Limited Power of Attorney, dated May 20, 2026, designates Michael D. Grover, Sandra L. Byers, and William Jack Plants II as attorneys-in-fact. This power of attorney authorizes them to complete and sign any necessary Section 16 reporting forms (Forms 3, 4, and 5) related to Finch's holdings and transactions in the securities of Financial Institutions, Inc., and to file these with the SEC. The authority granted will remain in effect until Finch is no longer required to file such forms or until explicitly revoked in writing. Finch acknowledges that his designated attorneys-in-fact are not assuming his compliance responsibilities under Section 16 of the Exchange Act.