31751 -- U.S. ZIP code Municipality (1990): FORT GAINES, Georgia All ZIPs for this municipality (1990): 31751 Population (2000): 2486 Housing Units (2000): 1423 Land area (2000): 116.889677 sq. miles (302.742861 sq. km) Water area (2000): 0.175084 sq. miles (0.453466 sq. km) Total area (2000): 117.064761 sq. miles (303.196327 sq. km) Located within: Georgia (GA) Location: 31.631333 N, 85.032419 W