ACV Auctions Inc

For the 2025 Annual Meeting of Shareholders

This proxy statement (this “Proxy Statement”) is furnished in connection with the solicitation by ACV Auctions Inc. (“we,” “us,” “our,” “ACV,” “ACV Auctions,” or the “Company”) on behalf of the Board of Directors (the “Board” or the “Board of Directors”) of proxies for use at the 2025 Annual Meeting of Shareholders of the Company to be held virtually on Wednesday, May 28, 2025 at 4:00 p.m. Eastern Time, at www.proxydocs.com/ACVA (the “2025 Annual Meeting”.)

IMPORTANT NOTICE REGARDING THE INTERNET AVAILABILITY OF PROXY MATERIALS FOR THE ANNUAL MEETING OF SHAREHOLDERS TO BE HELD ON MAY 28, 2025

We have elected to provide access to our proxy materials over the internet under the Securities and Exchange Commission’s (“SEC”) “notice and access” rules. We believe electronic delivery will expedite the receipt of materials and will help lower costs and reduce the environmental impact of our annual meeting materials. Accordingly, we have sent you a Notice of Internet Availability of Proxy Materials (the “Notice”).

The Notice will provide instructions as to how shareholders may access and review the proxy materials, including the Notice of Annual Meeting of Shareholders, this Proxy Statement, and the 2024 Annual Report on Form 10-K, on the website referred to in the Notice or, alternatively, how to request that a copy of the proxy materials, including a proxy card, be sent to them by mail. The Notice will also provide voting instructions. Please note that, while our proxy materials are available at the website referenced in the Notice, and our Notice of Annual Meeting of Shareholders, this Proxy Statement and the 2024 Annual Report on Form 10-K are available on investors.acvauto.com, no other information contained on either website is incorporated by reference in or considered to be a part of this document.

We intend to mail the Notice on or about April 17, 2025 to all shareholders of record entitled to vote at the Annual Meeting. The proxy materials, including the Notice of Annual Meeting of Shareholders, this Proxy Statement, and the Annual Reporton Form 10-K for the year ended December 31, 2024 will be made available to shareholders on www.proxydocs.com/ACVA on the same date.