Mequon, WI -- U.S. city in Wisconsin Population (2000): 21823 Housing Units (2000): 8162 Land area (2000): 46.183114 sq. miles (119.613712 sq. km) Water area (2000): 0.634635 sq. miles (1.643697 sq. km) Total area (2000): 46.817749 sq. miles (121.257409 sq. km) FIPS code: 51150 Located within: Wisconsin (WI), FIPS 55 Location: 43.224243 N, 87.960094 W ZIP Codes (1990): 53092 Note: some ZIP codes may be omitted esp. for suburbs. Headwords: Mequon, WI Mequon