31905 -- U.S. ZIP code Municipality (1990): CUSTER TERRACE, Georgia All ZIPs for this municipality (1990): 31905 Population (2000): 23421 Housing Units (2000): 4215 Land area (2000): 31.125819 sq. miles (80.615497 sq. km) Water area (2000): 0.069540 sq. miles (0.180107 sq. km) Total area (2000): 31.195359 sq. miles (80.795604 sq. km) Located within: Georgia (GA) Location: 32.373490 N, 84.906128 W