Total Population in St. Clair County, IL

ACS 2024 5-Year Estimates

Total Population
253,694
Rank #284 of 3,222
91th percentile

How St. Clair County Compares

St. Clair County
253,694
Illinois Average
253,694
Rank #9 of 102 in state
National
330M
99.9% below

National Distribution

Where St. Clair County falls among all 3,222 U.S. counties for total population.

33 9,808,667

■ St. Clair County: 253,694

Ranking Context

Rank County Value
#281 Washington County, AR 256,765
#282 Sussex County, DE 255,626
#283 Jefferson County, TX 253,878
#284 St. Clair County, IL 253,694
#285 Chesapeake city, VA 252,583
#286 Union County, NC 250,958
#287 Canyon County, ID 250,790
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Total Population in St. Clair County, Illinois

St. Clair County, Illinois has a total population of 253,694, which ranks #284 of 3,222 out of 3,222 counties nationwide. This is 99.9% below the national value of 330M.

Within Illinois, St. Clair County ranks #9 of 102 out of 102 counties. This places it in the 91th percentile nationally.

Total population count from the American Community Survey. 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.