62943 -- U.S. ZIP code Municipality (1990): GRANTSBURG, Illinois All ZIPs for this municipality (1990): 62943 Population (2000): 547 Housing Units (2000): 237 Land area (2000): 32.209501 sq. miles (83.422220 sq. km) Water area (2000): 0.134813 sq. miles (0.349164 sq. km) Total area (2000): 32.344314 sq. miles (83.771384 sq. km) Located within: Illinois (IL) Location: 37.342538 N, 88.733814 W