Columbia County, Wisconsin

Columbia County
Columbia County courthouse in December 2014
Location within the U.S. state of Wisconsin
Wisconsin's location within the U.S.
Coordinates: 43°28′N 89°20′W / 43.47°N 89.33°W / 43.47; -89.33
Country United States
State Wisconsin
Founded1846
Named afterChristopher Columbus
SeatPortage
Largest cityPortage
Area
  Total
796 sq mi (2,060 km2)
  Land766 sq mi (1,980 km2)
  Water30 sq mi (80 km2)  3.8%
Population
 (2020)
  Total
58,490
  Estimate 
(2023)
58,091
  Density73/sq mi (28/km2)
Time zoneUTC−6 (Central)
  Summer (DST)UTC−5 (CDT)
Congressional district6th
Websitewww.co.columbia.wi.us

Columbia County is a county located in the U.S. state of Wisconsin. As of the 2020 census, the population was 58,490. Its county seat and largest city is Portage. The county was created in 1846 as part of Wisconsin Territory. Columbia County is part of the Madison, WI Metropolitan Statistical Area as well as the Madison-Janesville-Beloit, WI Combined Statistical Area.