Buffalo County's 2026 population is estimated at 1,707, reflecting a -3.34% growth rate over the past year (World Population Review estimate based on U.S. Census Bureau data). Buffalo County is the 61st largest county in South Dakota. The 2010 population was 1,934 and has grown -11.74% since 2010.
Data after 2023 is projected based on recent change
Overall: 22.8 years
Female: 25.9 years
Male: 21.4 years
There are 1,100 adults, (166 of whom are seniors) in Buffalo County.
Female: 798 (44.1%)
Male: 1,010 (55.9%)
The racial composition of Buffalo County includes 78.98% Native American, 17.48% White, and smaller percentages for Two or more races, other race and multiracial populations.
| Race | Population ↓ | Percentage (of total) |
|---|---|---|
| Native American | 1,428 | 78.98% |
| White | 316 | 17.48% |
| Two or more races | 47 | 2.6% |
| Other race | 17 | 0.94% |
Buffalo County 's average per capita income is $39,412. Household income levels show a median of $47,045. The poverty rate stands at 33.91%.
| Name | Median ↓ | Mean |
|---|---|---|
| Married Families | $90,833 | - |
| Families | $59,615 | $69,142 |
| Households | $47,045 | $57,605 |
| Non Families | $15,000 | $34,574 |
Average Income
Median Household Income
Poverty Rate