Onalaska, Wisconsin

Onalaska, Wisconsin
Downtown Onalaska
Nickname: 
Ona
Location of Onalaska in La Crosse County, Wisconsin.
Onalaska
Onalaska
CountryUnited States
StateWisconsin
CountyLa Crosse
Established1851
Founded byThomas G. Rowe
Government
 • MayorKim Smith
Area
 • Total
10.98 sq mi (28.43 km2)
 • Land10.38 sq mi (26.88 km2)
 • Water0.60 sq mi (1.55 km2)
Elevation
700 ft (210 m)
Population
 (2020)
 • Total
18,803
 • Estimate 
(2022)
18,975
 • Density1,825.3/sq mi (704.77/km2)
Time zoneUTC−6 (Central)
 • Summer (DST)UTC−5 (Central)
Zipcode
54650
Area code608
FIPS code55-59925
Public TransitLa Crosse MTU
Websitewww.onalaskawi.gov

Onalaska (/ˌɒnəˈlæskə/ ON-ə-LASS-kə) is a city in La Crosse County, Wisconsin, United States. The population was 18,803 at the 2020 census. It is a principal city of the La Crosse–Onalaska metropolitan area.

Onalaska is built on a slightly elevated ridge above the Black River. Natural areas include both river bottom land and high, heavily wooded, scenic bluffs. A man-made reservoir at the city's western edge is known as Lake Onalaska. Onalaska is known as "The Sunfish Capital of the World."