Mills -- U.S. County in Iowa Population (2000): 14547 Housing Units (2000): 5671 Land area (2000): 436.533506 sq. miles (1130.616543 sq. km) Water area (2000): 3.134918 sq. miles (8.119401 sq. km) Total area (2000): 439.668424 sq. miles (1138.735944 sq. km) Located within: Iowa (IA), FIPS 19 Location: 41.030434 N, 95.642009 W Headwords: Mills Mills, IA Mills County Mills County, IA