Business First Bancshares, Inc.

proxy statement/prospectus or any other documents that BFST and Progressive may send to their respective shareholders in connection with the proposed transaction. This communication does not constitute an offer to sell or the solicitation of an offer to buy any securities. In connection with the proposed transaction between BFST and Progressive, BFST will file with the SEC a Registration Statement on Form S-4 (the “Registration Statement”), which will include a proxy statement of Progressive and a prospectus of BFST, as well as other relevant documents concerning the proposed transaction. Before making any voting or investment decisions, investors and shareholders are urged to read carefully the Registration Statement and the proxy statement/prospectus regarding the proposed transaction, as well as any other relevant documents filed with the SEC and any amendments or supplements to those documents, because they will contain important information. Progressive will mail the proxy statement/prospectus to its shareholders. Shareholders are also urged to carefully review and consider BFST’s public filings with the SEC, including, but not limited to, its proxy statements, its Annual Reports on Form 10-K, its Quarterly Reports on Form 10-Q, and its Current Reports on Form 8-K. Copies of the Registration Statement and proxy statement/prospectus and other filings incorporated by reference therein, as well as other filings containing information about BFST, may be obtained, free of charge, as they become available at the SEC’s website at www.sec.gov. You will also be able to obtain these documents, when they are filed, free of charge, from BFST at www.b1BANK.com. Copies of the proxy statement/prospectus can also be obtained, when they become available, free of charge, by directing a request to Business First Bancshares, Inc., 500 Laurel Street, Suite 101, Baton Rouge, LA 70801, Attention: Corporate Secretary, Telephone: 225-248-7600. Participants in the Solicitation BFST, Progressive and certain of their respective directors, executive officers and employees may, under the SEC’s rules, be deemed to be participants in the solicitation of proxies of Progressive’s shareholders in connection with the proposed transaction. Information about BFST’s directors and executive officers is available in its definitive proxy statement relating to its 2025