St. Clair County's estimated 2025 population is 9,953 with a growth rate of 1.07% in the past year according to the most recent United States census data. St. Clair County is the 85th largest county in Missouri. The 2010 population was 9,823 and has seen a growth of 1.32% since that time.
Data after 2023 is projected based on recent change
The racial composition of St. Clair County includes 93.56% White, and smaller percentages for other race, Black or African American, Asian, Native American and multiracial populations.
White (93.56%)
Two or more races (4.51%)
Other race (0.79%)
Black or African American (0.78%)
Asian (0.24%)
Native American (0.12%)
Race | Population | Percentage (of total) |
|---|---|---|
| White | 8,842 | 93.56% |
| Two or more races | 426 | 4.51% |
| Other race | 75 | 0.79% |
| Black or African American | 74 | 0.78% |
| Asian | 23 | 0.24% |
| Native American | 11 | 0.12% |
Married
Widowed
Divorced
Separated
Never Married
St. Clair County's average per capita income is $33,801. Household income levels show a median of $46,731. The poverty rate stands at 16.28%.
Name | Median | Mean |
|---|---|---|
| Married Families | $67,451 | - |
| Families | $61,803 | $74,132 |
| Households | $46,731 | $60,329 |
| Non Families | $30,722 | $38,339 |
Average Income
Median Household Income
Poverty Rate