Dewey County's 2026 population is estimated at 5,456, reflecting a 0.68% growth rate over the past year (World Population Review estimate based on U.S. Census Bureau data). Dewey County is the 33rd largest county in South Dakota. The 2010 population was 5,325 and has grown 2.46% since 2010.
Overall: 27.7 years
Female: 29 years
Male: 25.7 years
There are 3,209 adults, (518 of whom are seniors) in Dewey County.
Female: 2,603 (50%)
Male: 2,602 (50%)
The racial composition of Dewey County includes 74.2% Native American, 21.02% White, and smaller percentages for Black or African American, Asian and multiracial populations.
| Race | Population ↓ | Percentage (of total) |
|---|---|---|
| Native American | 3,862 | 74.2% |
| White | 1,094 | 21.02% |
| Two or more races | 219 | 4.21% |
| Black or African American | 27 | 0.52% |
| Asian | 3 | 0.06% |
Dewey County 's average per capita income is $39,533. Household income levels show a median of $54,104. The poverty rate stands at 33.04%.
| Name | Median ↓ | Mean |
|---|---|---|
| Married Families | $96,786 | - |
| Families | $62,926 | $75,582 |
| Households | $54,104 | $68,205 |
| Non Families | $34,655 | $45,493 |
Average Income
Median Household Income
Poverty Rate