St. Clair County, Missouri Demographics 2026

Population Overview

St. Clair County is located in Missouri with a total population of 9,451. It is the 89th most populous county out of 115 in Missouri.

Age Demographics

The median age in St. Clair County is 47.2 years. This is 21% higher than the state median of 38.9 years. 11.3% of residents are 75 or older, suggesting a significant retirement-age population with implications for healthcare services and senior housing.

Economy, Income & Housing

The median household income in St. Clair County is $46,731. This is 32% lower than the state median of $68,920. Compared to the national median of $78,538, household income here is 40% lower. The poverty rate stands at 16.3%. This is 29% higher than the state poverty rate of 12.6%. The unemployment rate is 2.5%. This is 40% lower than the state rate of 4.1%. The median home value is $142,500. Housing costs are 34% lower than the state median of $215,600. The home-value-to-income ratio is 3.0x. 75.7% of occupied housing units are owner-occupied. This homeownership rate is 11% higher than the state average of 67.9%.

Race & Ethnicity

St. Clair County has a predominantly White (non-Hispanic) population, comprising 92.9% of all residents. Hispanic or Latino residents account for 2.1%. The Black or African American population (0.8%) is well below the state average of 11.0%. The Hispanic or Latino population (2.1%) is well below the state average of 5.1%. The Asian population (0.2%) is well below the state average of 2.1%.

Education

13.7% of residents aged 25 and older hold a bachelor's degree or higher. This is 57% lower than the state rate of 31.9%. Nationally, 35.0% of adults hold at least a bachelor's degree. The high school graduation rate (or equivalent) is 87.9%.