60543 -- U.S. ZIP code Municipality (1990): OSWEGO, Illinois All ZIPs for this municipality (1990): 60543 Population (2000): 18769 Housing Units (2000): 6597 Land area (2000): 45.671841 sq. miles (118.289519 sq. km) Water area (2000): 0.103386 sq. miles (0.267769 sq. km) Total area (2000): 45.775227 sq. miles (118.557288 sq. km) Located within: Illinois (IL) Location: 41.684896 N, 88.341775 W