Stockholder Meeting Notice Greene County Bancorp, Inc.’s Annual Meeting of Stockholders will be held on November 2, 2024 at
Columbia-Greene Community College, 4400 Route 23, Hudson, New York 12534, at 10:00 a.m. Eastern Standard Time. Proposals to be voted on at the meeting are listed below along with the Board of Directors’ recommendations. The Board of Directors
recommend a vote FOR the nominees listed and FOR Proposal 2 and Proposal 3. 1. Election of Directors: 01 – Jay P. Cahalan 02 – Christopher Cannucciari 03 – Michelle M. Plummer, CPA,
CGMA 04 – Charles H. Schaefer, Esq. 2. The ratification of the appointment of Bonadio & Co, LLP as the independent registered public accounting firm for the Company for the fiscal year ending June 30, 2025. 3. To consider and approve a
non-binding advisory resolution regarding the compensation of the Company’s named executive officers. PLEASE NOTE – YOU CANNOT VOTE BY RETURNING THIS NOTICE. To vote your shares you must go online or request a paper copy of the proxy materials to
receive a proxy card. If you wish to attend and vote at the meeting, please bring this notice with you. Here’s how to order a copy of the proxy materials and select delivery preferences: Current and future delivery requests can be submitted using
the options below. If you request an email copy, you will receive an email with a link to the current meeting materials. PLEASE NOTE: You must use the number in the shaded bar on the reverse side when requesting a copy of the proxy materials.
Internet – Go to www.envisionreports.com/GCBC. Click Cast Your Vote or Request Materials. Phone – Call us free of charge at 1-866-641-4276. Email – Send an email to
[email protected] with “Proxy Materials Greene County Bancorp, Inc.”
in the subject line. Include your full name and address, plus the number located in the shaded bar on the reverse side, and state that you want a paper copy of the meeting materials. To facilitate timely delivery, all requests for a paper copy of
proxy materials must be received by October 18, 2024.