St. Clair County, Illinois
St. Clair County, Illinois, had an estimated population of 250,708 in 2025 across 1,704 km². The figures below come from the US Census Bureau's population estimates and the American Community Survey, each shown with its own vintage and its rank among Illinois's counties and nationally.
- Population
- 250,708
- 2025 estimate
- Area
- 1,704 km²
- Density
- 147
- per km²
- Median income
- $73,854
- household, ACS 2024
- Median age
- 39.9
- years, ACS 2024
How Illinois's counties spread
Amenities & Infrastructure
| Indicator | Value | In Illinois | In the US |
|---|---|---|---|
| Households with Broadband2024 | 89.7% | 24 / 102 | 901 / 3,144 |
| Median Gross Rent2024 | $1,090 | 10 / 102 | 745 / 3,137 |
| Median Home Value2024 | $180,300 | 23 / 102 | 1,637 / 3,139 |
| Owner-Occupied Homes2024 | 68.4% | 92 / 102 | 2,394 / 3,144 |
| Vacant Homes2024 | 12.8% | 28 / 102 | 1,753 / 3,144 |
Demography
| Indicator | Value | In Illinois | In the US |
|---|---|---|---|
| Aged 65 and Over2024 | 17.3% | 88 / 102 | 2,331 / 3,144 |
| American Indian & Alaska Native2024 | 0.2% | 10 / 102 | 1,145 / 3,144 |
| Asian, non-Hispanic2024 | 1.6% | 18 / 102 | 657 / 3,144 |
| Average Household Size2024people | 2.5 | 23 / 102 | 1,276 / 3,144 |
| Black, non-Hispanic2024 | 27.7% | 3 / 102 | 325 / 3,144 |
| Foreign-Born2024 | 3.3% | 26 / 102 | 1,416 / 3,144 |
| Hispanic or Latino2024 | 5.1% | 37 / 102 | 1,564 / 3,144 |
| Median Age2024years | 39.9 | 82 / 102 | 2,059 / 3,144 |
| Sex Ratio2024per 1,000 males | 1,061 | 3 / 102 | 369 / 3,144 |
| Speak a Language Other Than English2024 | 5.0% | 33 / 102 | 1,702 / 3,144 |
| Under 182024 | 23.0% | 19 / 102 | 1,058 / 3,144 |
| Veterans2024 | 11.5% | 1 / 102 | 176 / 3,144 |
| White, non-Hispanic2024 | 59.1% | 98 / 102 | 2,456 / 3,144 |
Economy
| Indicator | Value | In Illinois | In the US |
|---|---|---|---|
| Below Poverty Line2024 | 13.6% | 39 / 102 | 1,473 / 3,144 |
| Households on SNAP2024 | 16.2% | 27 / 102 | 766 / 3,144 |
| Income Inequality2024index | 0.452 | 24 / 102 | 1,326 / 3,144 |
| Median Household Income2024 | $73,854 | 29 / 102 | 926 / 3,143 |
| Per Capita Income2024 | $38,942 | 29 / 102 | 953 / 3,144 |
| Unemployment Rate2024 | 6.0% | 18 / 102 | 620 / 3,144 |
Education
| Indicator | Value | In Illinois | In the US |
|---|---|---|---|
| Bachelor's Degree or Higher2024 | 31.8% | 17 / 102 | 628 / 3,144 |
| High School or Higher2024 | 93.5% | 23 / 102 | 628 / 3,144 |
Health Coverage
| Indicator | Value | In Illinois | In the US |
|---|---|---|---|
| No Health Insurance2024 | 5.1% | 49 / 102 | 2,483 / 3,144 |
| With a Disability2024 | 15.2% | 57 / 102 | 1,794 / 3,144 |
Population & Density
| Indicator | Value | In Illinois | In the US |
|---|---|---|---|
| Population2025 | 250,708 | 9 / 102 | 294 / 3,144 |
| Population Density2025/km² | 147 | 9 / 102 | 357 / 3,144 |
Work & Commute
| Indicator | Value | In Illinois | In the US |
|---|---|---|---|
| Commute by Public Transit2024 | 1.6% | 7 / 102 | 226 / 3,144 |
| Households with No Vehicle2024 | 7.5% | 28 / 102 | 652 / 3,144 |
| Mean Commute Time2024minutes | 24 | 53 / 102 | 1,593 / 3,143 |
| Work from Home2024 | 12.4% | 16 / 102 | 718 / 3,144 |
Other counties of Illinois
- Adams County
- Alexander County
- Bond County
- Boone County
- Brown County
- Bureau County
- Calhoun County
- Carroll County
- Cass County
- Champaign County
- Christian County
- Clark County
- Clay County
- Clinton County
- Coles County
- Cook County
- Crawford County
- Cumberland County
- De Witt County
- DeKalb County
- Douglas County
- DuPage County
- Edgar County
- Edwards County
- Effingham County
- Fayette County
- Ford County
- Franklin County
- Fulton County
- Gallatin County
- Greene County
- Grundy County
- Hamilton County
- Hancock County
- Hardin County
- Henderson County
- Henry County
- Iroquois County
- Jackson County
- Jasper County
- Jefferson County
- Jersey County
- Jo Daviess County
- Johnson County
- Kane County
- Kankakee County
- Kendall County
- Knox County
- LaSalle County
- Lake County
- Lawrence County
- Lee County
- Livingston County
- Logan County
- Macon County
- Macoupin County
- Madison County
- Marion County
- Marshall County
- Mason County
- Massac County
- McDonough County
- McHenry County
- McLean County
- Menard County
- Mercer County
- Monroe County
- Montgomery County
- Morgan County
- Moultrie County
- Ogle County
- Peoria County
- Perry County
- Piatt County
- Pike County
- Pope County
- Pulaski County
- Putnam County
- Randolph County
- Richland County
- Rock Island County
- Saline County
- Sangamon County
- Schuyler County
- Scott County
- Shelby County
- Stark County
- Stephenson County
- Tazewell County
- Union County
- Vermilion County
- Wabash County
- Warren County
- Washington County
- Wayne County
- White County
- Whiteside County
- Will County
- Williamson County
- Winnebago County
- Woodford County
Compare St. Clair County against every other county on a map, add layers and run a scatter — open the atlas. Sources and vintages for every figure on this page are listed under datasets, or browse all 3,144 counties.