County in Illinois · 561 sq mi · 27 people per sq mi
15,166 people live in Mercer County. The typical household earns $74,182, and the median resident is 44.7 years old.
2026 projection
From 15,637 in 2020
Poverty rate 8.92%
Men 44.2 · Women 45.1
1830–2026
15,166
2026 projection
3% since 2020 (decrease)
Source: U.S. Census Bureau decennial counts and annual estimates. 2026 is a projection. Values between recorded years are interpolated.
Use the left and right arrow keys to inspect population observations.
1830–2026
15,166
2026 projection
3% since 2020 (decrease)
Source: U.S. Census Bureau decennial counts and annual estimates. 2026 is a projection. Values between recorded years are interpolated.
Use the left and right arrow keys to inspect population observations.
| 2026 | 15,166 | -63 | 0.41% |
|---|---|---|---|
| 2025 | 15,229 | -63 | 0.41% |
| 2024 | 15,292 | -180 | 1.16% |
| 2023 | 15,472 | -39 | 0.25% |
| 2022 | 15,511 | -76 | 0.49% |
| 2021 | 15,587 | -50 | 0.32% |
| 2020 | 15,637 | +147 | 0.95% |
| 2019 | 15,490 | -82 | 0.53% |
| 2018 | 15,572 | -46 | 0.29% |
| 2017 | 15,618 | +7 | 0.04% |
Showing 10 of 34 years.
U.S. Census Bureau, 2024 ACS 5-year estimates · Table S0101
Each square is about 1% of residents (roughly 155 people).
Hispanic or Latino residents can be of any race. All other groups exclude Hispanic residents.
U.S. Census Bureau, 2024 ACS 5-year estimates · Table B03002
Half of households earn more, half earn less
Typical yearly pay for a worker 25 or older.
About 1 in 11 residents
62% of residents age 15 and older are married.
| Status | Overall | Male | Female |
|---|---|---|---|
| Married | 62% | 62% | 62% |
| Never married | 23% | 26% | 19% |
| Divorced | 8% | 7% | 9% |
| Widowed | 6% | 4% | 9% |
| Separated | 1% | 2% | <1% |
U.S. Census Bureau, 2024 ACS 5-year estimates · Table S1201
8 sources, all from the U.S. Census Bureau