Whiteside County's 2026 population is estimated at 54,807, reflecting a 0.14% growth rate over the past year (World Population Review estimate based on U.S. Census Bureau data). Whiteside County is the 24th largest county in Illinois. The 2010 population was 58,489 and has grown -6.3% since 2010.
Data after 2023 is projected based on recent change
Overall: 43 years
Female: 44.5 years
Male: 41.5 years
There are 42,882 adults, (11,967 of whom are seniors) in Whiteside County.
Female: 27,532 (50.1%)
Male: 27,415 (49.9%)
The racial composition of Whiteside County includes 85.12% White, 3.12% other race, and smaller percentages for Black or African American, Asian, Native American, Native Hawaiian or Pacific Islander and multiracial populations.
| Race | Population ↓ | Percentage (of total) |
|---|---|---|
| White | 46,769 | 85.12% |
| Two or more races | 5,273 | 9.6% |
| Other race | 1,714 | 3.12% |
| Black or African American | 691 | 1.26% |
| Asian | 291 | 0.53% |
| Native American | 206 | 0.37% |
| Native Hawaiian or Pacific Islander | 3 | 0.01% |
Whiteside County 's average per capita income is $46,426. Household income levels show a median of $67,500. The poverty rate stands at 11.98%.
| Name | Median ↓ | Mean |
|---|---|---|
| Married Families | $105,683 | $119,427 |
| Families | $86,228 | $102,741 |
| Households | $67,500 | $86,592 |
| Non Families | $38,737 | $53,468 |
Average Income
Median Household Income
Poverty Rate
