31057 -- U.S. ZIP code Municipality (1990): MARSHALLVILLE, Georgia All ZIPs for this municipality (1990): 31057 Population (2000): 2079 Housing Units (2000): 857 Land area (2000): 92.868785 sq. miles (240.529038 sq. km) Water area (2000): 0.184916 sq. miles (0.478929 sq. km) Total area (2000): 93.053701 sq. miles (241.007967 sq. km) Located within: Georgia (GA) Location: 32.446656 N, 83.934132 W