Illinois City is located in Illinois. Illinois City, Illinois has a population of 1,255. Illinois City is less family-centric than the surrounding county with 26% households with children. The county percentage for households with children is 26%.
The median household income in Illinois City, Illinois is $76,645. The median household income for the surrounding county is $57,012 compared to the national median of $66,222. The median age of people living in Illinois City is 50.5 years.
The average high temperature in July is 85.41 degrees, with an average low temperature in January of 11.97 degrees. The annual precipitation is 35.57.