X0609 4 2026-06-25 0001624322 Business First Bancshares, Inc. BFST 0001734794 MOCKLER PATRICK E. false 500 LAUREL STREET, SUITE 101 BATON ROUGE LA 70801 1 0 COMMON STOCK 2026-06-26 4 M 0 1016 A 33158.50 D COMMON STOCK 30888.472 I By: Rita Gardner Mockler Estate Account Restricted Stock Units 0 2026-06-25 4 A 0 998 A Common Stock 998 2014 D Restricted Stock Units 2026-06-26 4 M 0 1016 D Common Stock 1016 998 D Reflects the grant of time-based restricted stock units to the reporting person under the Business First Bancshares, Inc. 2024 Equity Incentive Plan on June 25, 2026. The time-based restricted stock units will fully vest on June 25, 2027. Each time-based restricted stock unit is economically equivalent to one share of common stock of the issuer. Under the terms of the relevant restricted stock unit grant, the reported unvested restricted stock units are subject to forfeiture upon the occurrence of certain events. The reporting person received an award of 1,016 time-based restricted stock units on June 26, 2025, vesting on the first anniversary of the issuance date. Represents the holdings of the Rita Gardner Mockler Estate account, of which the reporting person is the executor. The reporting person disclaims beneficial ownership of the common stock held by the Rita Garnder Mockler Estate account except to the extent of his pecuniary interest therein. /s/ Heather Roemer, as attorney-in-fact for Patrick E. Mockler 2026-06-29