How St. Clair County Compares

St. Clair County

39.9 years

Illinois Average

39.9 years

Rank #82 of 102 in state

National

38.9 years

2.6% above

National Distribution

Where St. Clair County falls among all 3,222 U.S. counties for median age.

21.4 years 86.2 years

■ St. Clair County: 39.9 years

Ranking Context

Rank	County	Value
#2,139	Jeff Davis County, GA	39.9 years
#2,140	Madison County, GA	39.9 years
#2,141	Pike County, GA	39.9 years
#2,142	St. Clair County, IL	39.9 years
#2,143	Benton County, IN	39.9 years
#2,144	Clark County, IN	39.9 years
#2,145	Marion County, IA	39.9 years

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Median Age in St. Clair County, Illinois

St. Clair County, Illinois has a median age of 39.9 years, which ranks #2,142 of 3,222 out of 3,222 counties nationwide. This is 2.6% above the national value of 38.9 years.

Within Illinois, St. Clair County ranks #82 of 102 out of 102 counties. This places it in the 34th percentile nationally.

The median age of the total population. All data comes from the U.S. Census Bureau's American Community Survey (ACS) 5-Year Estimates for 2024.

About this data

Source: U.S. Census Bureau, American Community Survey 5-Year Estimates (2024). All values are estimates derived from survey samples and are subject to margin of error. For more information, see our methodology.