County Dossier
St. Clair County
Illinois | County
Population
253,694
Land Area
657.7 sq mi
Context
Metro
Geography
County silhouette
- Land Area
- 657.7 sq mi
- Water Area
- 16.1 sq mi
- Water Share
- 2.4%
Terrain Layer
Open the county terrain view inside the atlas flow.
Population & Housing
Population
253,694
- Density
- 385.7 / sq mi
- Households
- 100,846
- Housing Units
- 115,630
- Median Age
- 39.9 years
Income & Economy
Median Household Income
$73,854
GDP
$16.13B
Real GDP Change+1.1%
- Per Capita Income
- $38,942
- Personal Income
- $15.50B
- Personal Income Per Capita
- $61,712
Classification
RUCC 1
Metro
Counties in metro areas of 1 million population or more
Relief
Min
135 ft
Mean
471 ft
Max
725 ft