961 Oak Street, Beloit, Wisconsin 53511-5116 | 608.346.3462
Janesville is a city in Rock County, Wisconsin, United States. It is the county seat and largest city in the county. It is a principal municipality of the Janesville, Wisconsin, Metropolitan Statistical Area and is included in the Madison–Janesville–Beloit, WI Combined Statistical Area. As of the 2020 census, the city had a population of 65,615.