Duncan is a city located in Stephens County, Oklahoma. Duncan has a 2025 population of 23,304 . It is also the county seat of Stephens County . Duncan is currently growing at a rate of 0.56% annually and its population has increased by 2.87% since the most recent census, which recorded a population of 22,653 in 2020.
The average household income in Duncan is $80,585 with a poverty rate of 20.42%. The median age in Duncan is 40 years: 38.2 years for males, and 41.9 years for females. For every 100 females there are 94.6 males.
Data after 2023 is projected based on recent change
The racial composition of Duncan includes 77.96% White, 3.38% Native American, and smaller percentages for other race, Black or African American, Asian, Native Hawaiian or Pacific Islander and multiracial populations.
White (77.96%)
Two or more races (12.67%)
Native American (3.38%)
Other race (2.92%)
Black or African American (2.54%)
Asian (0.48%)
Native Hawaiian or Pacific Islander (0.04%)
Race | Population | Percentage (of total) |
|---|---|---|
| White | 17,832 | 77.96% |
| Two or more races | 2,897 | 12.67% |
| Native American | 773 | 3.38% |
| Other race | 668 | 2.92% |
| Black or African American | 582 | 2.54% |
| Asian | 110 | 0.48% |
| Native Hawaiian or Pacific Islander | 10 | 0.04% |
Married
Widowed
Divorced
Separated
Never Married
Duncan's average per capita income is $39,449. Household income levels show a median of $57,020. The poverty rate stands at 20.42%.
Name | Median | Mean |
|---|---|---|
| Married Families | $85,493 | - |
| Families | $70,605 | $96,548 |
| Households | $57,020 | $80,585 |
| Non Families | $30,765 | $45,977 |
Average Income
Median Household Income
Poverty Rate