62321 -- U.S. ZIP code Municipality (1990): CARTHAGE, Illinois All ZIPs for this municipality (1990): 62321 Population (2000): 4328 Housing Units (2000): 1976 Land area (2000): 166.391274 sq. miles (430.951402 sq. km) Water area (2000): 0.219976 sq. miles (0.569735 sq. km) Total area (2000): 166.611250 sq. miles (431.521137 sq. km) Located within: Illinois (IL) Location: 40.414128 N, 91.115779 W