Delavan is a city in Tazewell County, Illinois, United States.

It is a part of the Peoria, Illinois Metropolitan Statistical Area.

[3][4] The city derives its name from Edward C. Delavan, a temperance advocate from Albany, New York.

[6] According to the 2010 census, Delavan has a total area of 0.71 square miles (1.84 km2), all land.

24.7% of all households were made up of individuals, and 13.2% had someone living alone who was 65 years of age or older.