Winnebago is a village in Winnebago County, Illinois. It is part of the Rockford-Winnebago Metropolitan Statistical Area. The population was 3,101 at the 2010 census, up from 2,958 in 2000.

Winnebago County is a county located in the U.S. state of Illinois. According to the 2020 census, it had a population of 285,350 making it the seventh most populous county in Illinois behind Cook County and its five surrounding collar counties. Its county seat is Rockford. Winnebago County is the central county of the Rockford metropolitan area.