Waukesha County, Wisconsin

Waukesha County () is a county in the U.S. state of Wisconsin. As of the 2020 United States Census, the population was 406,978, making it the third-most populous county in Wisconsin. Its median income of $88,985 placed it as the only county in Wisconsin on the list of the 100 highest-income counties in the U.S. by median income as of 2020. Its county seat and largest city is Waukesha.

Waukesha County is included in the Milwaukee metropolitan area, and is one of the three WOW counties.