X0306 4 2021-04-30 0001624322 Business First Bancshares, Inc. BFST 0001736530 WHITE STEVEN GERARD 500 LAUREL STREET, SUITE 101 BATON ROUGE LA 70801 1 COMMON STOCK 7471 D COMMON STOCK 2021-04-30 4 S 0 3000 23.94 D 36749 I HELD BY WILLIAM A. ROBINSON TRUST This transaction was executed in multiple trades at prices ranging from $23.90 to $24.04. The price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected. Represents the holdings of William A. Robinson Private Foundation, of which the reporting person is the trustee. The reporting person disclaims beneficial ownership of registrant common stock held by William A. Robinson Private Foundation except to the extent of his pecuniary interest. /s/ Heather Roemer, as attorney-in-fact for Steven G. White 2021-05-03