Colchester, IL -- U.S. city in Illinois Population (2000): 1493 Housing Units (2000): 694 Land area (2000): 0.994842 sq. miles (2.576630 sq. km) Water area (2000): 0.000000 sq. miles (0.000000 sq. km) Total area (2000): 0.994842 sq. miles (2.576630 sq. km) FIPS code: 15378 Located within: Illinois (IL), FIPS 17 Location: 40.425174 N, 90.792339 W ZIP Codes (1990): 62326 Note: some ZIP codes may be omitted esp. for suburbs. Headwords: Colchester, IL Colchester