St. Clair County, IL has a population of 262,759 people with a median age of 38.7 and a median household income of $50,267. Between 2015 and 2016 the population of St. Clair County, IL declined from 264,052 to 262,759, a 0.49% decrease and its median household income declined from $50,347 to $50,267, a 0.16% decrease.
The population of St. Clair County, IL is N/A Other, N/A Two+, and N/A Hawaiian. N/A of the people in St. Clair County, IL speak a non-English language, and 98.3% are U.S. citizens.
The largest universities in St. Clair County, IL are Southwestern Illinois College, with 3,025 graduates, McKendree University, with 745 graduates, and Vatterott College-Fairview Heights, with 207 graduates.
The median property value in St. Clair County, IL is $132,700, and the homeownership rate is 63.3%. Most people in St. Clair County, IL commute by Drove Alone, and the average commute time is 24 minutes. The average car ownership in St. Clair County, IL is 2 cars per household.
St. Clair County, IL is the 9th most populated county in Illinois and borders Clinton County, IL; Madison County, IL; Monroe County, IL; Randolph County, IL; Washington County, IL; St. Louis County, MO; St. Louis city, MO& 2 more.