Located in the south central corner of the Madison Region and directly along the Wisconsin-Illinois border, Rock County is one of Wisconsin’s largest counties, both in square miles and population. With diversified strengths in manufacturing, food processing, and logistics, Rock County is positioned along the I-39 corridor and offers easy marketplace access and exposure. Paired with affordable cost of living standards and high quality of life, Rock County is a powerful economic engine for the state and region.

2010 Population: 160,331
2015 Population Estimate: 161,448

Demographics of Rock County

Labor Force
Labor Force Profile of Rock County

Major Employers
Top private-sector employers in Rock County include Frito Lay, Hormel Foods, Le Mans Corp, Grainger, and Seneca Foods.

Rock County Major Employers

Colleges & Universities
University of Wisconsin – Rock County
Beloit College
Blackhawk Technical College

Large Communities

  • City of Janesville (county seat): 63,510
  • City of Beloit: 36,792
  • Town of Beloit: 7,625
  • Milton: 5,538
  • Edgerton: 5,521
  • Evansville: 5,135
  • Town of Janesville: 3,444
  • Brodhead: 3,285
  • Fulton: 3,269
  • Rock: 3,183

Economic Development Professional
Rock County Economic Development Alliance
James Otterstein, Economic Development Manager
608.757.5598 | Email James

Sources: U.S. Census; Wisconsin’s WORKnet; Municipality Population Estimates, Wisconsin Department of Administration, Demographic Services Center; Applied Geographic Solutions via LocateInWisconsin.


Download the Rock County Profile to learn more.