Williamson County's estimated 2026 population is 67,376 with a growth rate of 0.22% in the past year according to the most recent United States census data. Williamson County is the 22nd largest county in Illinois. The 2010 population was 66,440 and has seen a growth of 1.41% since that time.
Data after 2023 is projected based on recent change
Overall: 41.6 years
Female: 42.4 years
Male: 40.9 years
There are 52,649 adults, (13,136 of whom are seniors) in Williamson County.
Female: 33,291 (49.8%)
Male: 33,585 (50.2%)
The racial composition of Williamson County includes 88.95% White, 4.47% Black or African American, and smaller percentages for Asian, other race, Native American and multiracial populations.
Race | Population | Percentage (of total) |
|---|---|---|
| White | 59,489 | 88.95% |
| Black or African American | 2,988 | 4.47% |
| Two or more races | 2,987 | 4.47% |
| Asian | 1,000 | 1.5% |
| Other race | 226 | 0.34% |
| Native American | 186 | 0.28% |
Williamson County's average per capita income is $47,386. Household income levels show a median of $65,604. The poverty rate stands at 13.75%.
Name | Median | Mean |
|---|---|---|
| Married Families | $104,181 | $119,078 |
| Families | $87,344 | $103,881 |
| Households | $65,604 | $85,846 |
| Non Families | $37,577 | $52,966 |
Average Income
Median Household Income
Poverty Rate
