Quincy, IL -- U.S. city in Illinois Population (2000): 40366 Housing Units (2000): 18043 Land area (2000): 14.618846 sq. miles (37.862636 sq. km) Water area (2000): 0.026715 sq. miles (0.069191 sq. km) Total area (2000): 14.645561 sq. miles (37.931827 sq. km) FIPS code: 62367 Located within: Illinois (IL), FIPS 17 Location: 39.932335 N, 91.388737 W ZIP Codes (1990): 62301 Note: some ZIP codes may be omitted esp. for suburbs. Headwords: Quincy, IL Quincy