X0306 4 2019-03-12 0001624322 Business First Bancshares, Inc. BFST 0001734795 MELVILLE DAVID R. III 500 LAUREL STREET, SUITE 101 BATON ROUGE LA 70801 1 1 President and CEO Common Stock 2019-03-12 4 I 0 2067 24.19 A 21812 D Reflects reallocation of 401(k) assets by reporting person, pursuant to which reporting person acquired units of an employer stock fund available through issuer's 401(k) plan. Share numbers and price are on an approximately equivalent basis for units held in the fund as if investable cash equivalents held by the fund were fully invested in issuer common stock. Includes (a) 1,566 shares of unvested restricted stock granted on 03/31/2017 and (b) 7,370 shares of unvested restricted stock granted on 03/31/2018, in each case subject to vesting in three equal installments over a period of two years beginning on the grant date and subject to the terms of the relevant restricted stock grant. The reported shares of unvested restricted stock are subject to forfeiture upon the occurrence of certain events specified in the restricted stock grant. Includes units of employer stock fund through issuer's 401(k) plan equivalent to approximately 2,067 shares. /s/ Heather Roemer, as attorney-in-fact 2019-03-14