Winnebago County's 2026 population is estimated at 284,383, reflecting a 0.25% growth rate over the past year (World Population Review estimate based on U.S. Census Bureau data). Winnebago County is the 7th largest county in Illinois. The 2010 population was 295,090 and has grown -3.63% since 2010.
Overall: 39.6 years
Female: 40.3 years
Male: 38.7 years
There are 216,761 adults, (52,518 of whom are seniors) in Winnebago County.
Female: 144,704 (51.1%)
Male: 138,588 (48.9%)
The racial composition of Winnebago County includes 66.39% White, 12.04% Black or African American, 6.1% other race, and smaller percentages for Asian, Native American, Native Hawaiian or Pacific Islander and multiracial populations.
| Race | Population ↓ | Percentage (of total) |
|---|---|---|
| White | 188,087 | 66.39% |
| Black or African American | 34,098 | 12.04% |
| Two or more races | 33,580 | 11.85% |
| Other race | 17,280 | 6.1% |
| Asian | 8,280 | 2.92% |
| Native American | 1,849 | 0.65% |
| Native Hawaiian or Pacific Islander | 118 | 0.04% |
Winnebago County 's average per capita income is $46,733. Household income levels show a median of $65,837. The poverty rate stands at 15.62%.
| Name | Median ↓ | Mean |
|---|---|---|
| Married Families | $102,225 | $122,208 |
| Families | $83,365 | $102,686 |
| Households | $65,837 | $86,473 |
| Non Families | $40,000 | $55,741 |
Average Income
Median Household Income
Poverty Rate
