Mercer County's 2026 population is estimated at 14,964, reflecting a -1.08% growth rate over the past year (World Population Review estimate based on U.S. Census Bureau data). Mercer County is the 70th largest county in Illinois. The 2010 population was 16,410 and has grown -8.81% since 2010.
Data after 2023 is projected based on recent change
Overall: 44.7 years
Female: 45.1 years
Male: 44.2 years
There are 12,265 adults, (3,389 of whom are seniors) in Mercer County.
Female: 7,665 (49.5%)
Male: 7,830 (50.5%)
The racial composition of Mercer County includes 94.15% White, and smaller percentages for other race, Black or African American, Asian, Native American and multiracial populations.
| Race | Population ↓ | Percentage (of total) |
|---|---|---|
| White | 14,589 | 94.15% |
| Two or more races | 569 | 3.67% |
| Other race | 174 | 1.12% |
| Black or African American | 93 | 0.6% |
| Asian | 56 | 0.36% |
| Native American | 14 | 0.09% |
Mercer County 's average per capita income is $49,390. Household income levels show a median of $74,182. The poverty rate stands at 8.92%.
| Name | Median ↓ | Mean |
|---|---|---|
| Married Families | $102,819 | - |
| Families | $95,557 | $107,841 |
| Households | $74,182 | $92,846 |
| Non Families | $39,430 | $56,159 |
Average Income
Median Household Income
Poverty Rate
