Quincy is a city located in Adams County, Illinois. Quincy has a 2025 population of 38,588 . It is also the county seat of Adams County . Quincy is currently declining at a rate of -0.51% annually and its population has decreased by -2.49% since the most recent census, which recorded a population of 39,575 in 2020.
The average household income in Quincy is $76,426 with a poverty rate of 15.43%. The median age in Quincy is 40.1 years: 38.5 years for males, and 41.3 years for females. For every 100 females there are 92.7 males.
Data after 2023 is projected based on recent change
The racial composition of Quincy includes 87.22% White, 5.22% Black or African American, and smaller percentages for Asian, other race, Native American, Native Hawaiian or Pacific Islander and multiracial populations.
White (87.22%)
Two or more races (5.81%)
Black or African American (5.22%)
Asian (1.03%)
Other race (0.67%)
Native American (0.04%)
Native Hawaiian or Pacific Islander (0.01%)
Race | Population | Percentage (of total) |
|---|---|---|
| White | 34,181 | 87.22% |
| Two or more races | 2,278 | 5.81% |
| Black or African American | 2,045 | 5.22% |
| Asian | 404 | 1.03% |
| Other race | 264 | 0.67% |
| Native American | 14 | 0.04% |
| Native Hawaiian or Pacific Islander | 2 | 0.01% |
Married
Widowed
Divorced
Separated
Never Married
Quincy's average per capita income is $43,931. Household income levels show a median of $56,372. The poverty rate stands at 15.43%.
Name | Median | Mean |
|---|---|---|
| Married Families | $96,884 | - |
| Families | $80,172 | $98,732 |
| Households | $56,372 | $76,426 |
| Non Families | $39,835 | $50,175 |
Average Income
Median Household Income
Poverty Rate