Vandalia is located in Fayette county Illinois with a geographic area of 8.1 square miles. The total population in Vandalia is 6,615 with 59.1% male and 40.9% female. Children under age 5 represent 5.8% of the population, under age 18 equal 16.2% of the population and over age 65 is 16.0% of the population. The median household income is $35,862, per capita income is $17,994. There are a total of 2,253 housing units with 68.1% owner occupied. Education includes 39.4% of residents that are high school graduates and 13.0% with a bachelor's degree or higher. The average temperature in Vandalia in the summer is 75 degrees, and in the winter 27 degrees.
