MERCANTILE BANK CORP

A proxy is your designation of another person to vote on your behalf. The other person is called a proxy. If you designate someone as your proxy in a written document, that document also is called a proxy or a proxy card. When you designate a proxy, you also may direct the proxy how to vote your shares. We sometimes refer to this as your “proxy vote.” By completing and returning the enclosed proxy card, or voting by internet or telephone, you are giving the persons appointed as proxies by our Board of Directors the authority to vote your shares.

You may revoke your proxy and change your vote at any time before the proxy ballot is cast at the annual meeting. If you are a shareholder of record, you may revoke your proxy and change your vote by submitting a later-dated proxy by telephone, internet or mail, or by delivering to our Secretary a written notice of revocation prior to the meeting. Attending the virtual meeting will not revoke your proxy.

If you submit a signed proxy card or submit your proxy by telephone or internet and do not specify how you want to vote your shares, the proxies will vote your shares:

If you hold your shares in street name, contact your broker, bank, trust or other nominee regarding how to revoke your proxy and change your vote.

A proxy statement is a document that we are required to give you, or provide you access to, in accordance with regulations of the Securities and Exchange Commission (the “SEC”), when we ask you to designate proxies to vote your shares of our common stock at a meeting of our shareholders. The proxy statement includes information regarding the matters to be acted upon at the meeting and certain other information required by regulations of the SEC and rules of The NASDAQ Stock Market (“NASDAQ”).

12 | MERCANTILE BANK CORPORATION | 2026 PROXY STATEMENT