Warsaw, IL -- U.S. city in Illinois Population (2000): 1793 Housing Units (2000): 807 Land area (2000): 6.616576 sq. miles (17.136853 sq. km) Water area (2000): 0.871255 sq. miles (2.256541 sq. km) Total area (2000): 7.487831 sq. miles (19.393394 sq. km) FIPS code: 78942 Located within: Illinois (IL), FIPS 17 Location: 40.355173 N, 91.432928 W ZIP Codes (1990): 62379 Note: some ZIP codes may be omitted esp. for suburbs. Headwords: Warsaw, IL Warsaw