Collinsville is located in Madison county Illinois with a geographic area of 15.1 square miles. The total population in Collinsville is 24,489 with 46.5% male and 53.5% female. Children under age 5 represent 6.5% of the population, under age 18 equal 22.1% of the population and over age 65 is 14.7% of the population. The median household income is $56,250, per capita income is $31,912. There are a total of 10,479 housing units with 67.0% owner occupied. Education includes 28.3% of residents that are high school graduates and 28.1% with a bachelor's degree or higher. The average temperature in Collinsville in the summer is 74 degrees, and in the winter 27 degrees.
