A surgical stapling apparatus (10) having an adjustable minimum tissue gap (G) is provided. The surgical stapling apparatus (10) includes a proximal handle portion (20), an elongated central body portion (30), a distal head portion (40), an anvil assembly (50), and an approximation assembly (100). The approximation assembly (100) includes a drive screw (140), a screw stop (150), and a screw extension (160). The adjustable minimum tissue gap (G) can be adjusted by selectively securing the screw extension (160) to the drive screw (140) using a first or second pair of openings (145, 147) of the drive screw (140). A method is also provided to determine the minimum tissue gap (G) of the surgical stapling apparatus (10).