Portage, MI -- U.S. city in Michigan Population (2000): 44897 Housing Units (2000): 18880 Land area (2000): 32.203165 sq. miles (83.405811 sq. km) Water area (2000): 2.822819 sq. miles (7.311068 sq. km) Total area (2000): 35.025984 sq. miles (90.716879 sq. km) FIPS code: 65560 Located within: Michigan (MI), FIPS 26 Location: 42.209592 N, 85.588525 W ZIP Codes (1990): Note: some ZIP codes may be omitted esp. for suburbs. Headwords: Portage, MI Portage