60552 -- U.S. ZIP code Municipality (1990): SOMONAUK, Illinois All ZIPs for this municipality (1990): 60552 Population (2000): 3824 Housing Units (2000): 1479 Land area (2000): 24.550383 sq. miles (63.585198 sq. km) Water area (2000): 0.021957 sq. miles (0.056869 sq. km) Total area (2000): 24.572340 sq. miles (63.642067 sq. km) Located within: Illinois (IL) Location: 41.645998 N, 88.690002 W