Vandalia is located in Illinois. Vandalia, Illinois has a population of 6,827. Vandalia is more family-centric than the surrounding county with 26% households with children. The county percentage for households with children is 25%.
The median household income in Vandalia, Illinois is $40,155. The median household income for the surrounding county is $49,580 compared to the national median of $66,222. The median age of people living in Vandalia is 37.3 years.
The average high temperature in July is 87.5 degrees, with an average low temperature in January of 18 degrees. The annual precipitation is 38.9.