Washburn is a village mostly in Woodford County, with a small northerly portion in Marshall County, Illinois, United States. The population was 1,158 at the 2010 census, up from 1,147 in 2000. It is part of the Peoria, Illinois Metropolitan Statistical Area.Washburn is an agricultural community located in north-central Illinois. Illinois Route 89 forms the main north-south road through Washburn as Jefferson Street.