St. Clair County, IL — Demographics & Population
Population, age distribution, race & ethnicity, and education data
Population Overview
Source: Census Bureau ACS (2023)Total Population
254,777
Male
123,563
48.5%
Female
131,214
51.5%
Median Age
39.5 yrs
Avg Household Size
2.5
Foreign Born
3.2%
Race & Ethnicity
Source: Census Bureau ACS (2023)Age Distribution
Source: Census Bureau ACS (2023)Education
Source: Census Bureau ACS (2023)Bachelor's or Higher21.1%
High School or Higher39.6%
Other Demographics
Source: Census Bureau ACS (2023)Veterans
8.9%
Disability
0.0%
Non-English Home
5.0%
Married
38.6%
St. Clair County, IL has a population of 254,777 according to 2023 Census Bureau estimates. The median age is 39.5 years. The largest racial or ethnic group is White at 61.2% of the population. 21.1% of residents hold a bachelor's degree or higher. 3.2% of residents are foreign-born.