St. Clair County's estimated 2026 population is 10,109 with a growth rate of 1.33% 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 2.91% since that time.
Data after 2023 is projected based on recent change
Overall: 46.1 years
Female: 46 years
Male: 46.3 years
There are 7,549 adults, (2,457 of whom are seniors) in St. Clair County.
Female: 4,687 (48.9%)
Male: 4,900 (51.1%)
The racial composition of St. Clair County includes 93.46% White, and smaller percentages for Black or African American, other race, Asian, Native American and multiracial populations.
Race | Population | Percentage (of total) |
|---|---|---|
| White | 8,960 | 93.46% |
| Two or more races | 439 | 4.58% |
| Black or African American | 77 | 0.8% |
| Other race | 71 | 0.74% |
| Asian | 24 | 0.25% |
| Native American | 16 | 0.17% |
St. Clair County's average per capita income is $40,914. Household income levels show a median of $53,043. The poverty rate stands at 14.68%.
Name | Median | Mean |
|---|---|---|
| Married Families | $74,601 | - |
| Families | $69,120 | $84,894 |
| Households | $53,043 | $69,413 |
| Non Families | $31,647 | $40,044 |
Average Income
Median Household Income
Poverty Rate
