Decatur, MI -- U.S. village in Michigan Population (2000): 1838 Housing Units (2000): 792 Land area (2000): 1.149385 sq. miles (2.976893 sq. km) Water area (2000): 0.000000 sq. miles (0.000000 sq. km) Total area (2000): 1.149385 sq. miles (2.976893 sq. km) FIPS code: 21040 Located within: Michigan (MI), FIPS 26 Location: 42.109757 N, 85.973443 W ZIP Codes (1990): 49045 Note: some ZIP codes may be omitted esp. for suburbs. Headwords: Decatur, MI Decatur