Pennington County's 2026 population is estimated at 116,269, reflecting a 0.12% growth rate over the past year (World Population Review estimate based on U.S. Census Bureau data). Pennington County is the 2nd largest county in South Dakota. The 2010 population was 101,253 and has grown 14.83% since 2010.
Data after 2023 is projected based on recent change
Overall: 40.1 years
Female: 41.1 years
Male: 39.2 years
There are 88,537 adults, (22,870 of whom are seniors) in Pennington County.
Female: 55,604 (49%)
Male: 57,908 (51%)
The racial composition of Pennington County includes 79% White, 6.77% Native American, and smaller percentages for other race, Asian, Black or African American, Native Hawaiian or Pacific Islander and multiracial populations.
| Race | Population ↓ | Percentage (of total) |
|---|---|---|
| White | 89,672 | 79% |
| Two or more races | 11,871 | 10.46% |
| Native American | 7,690 | 6.77% |
| Other race | 1,578 | 1.39% |
| Asian | 1,401 | 1.23% |
| Black or African American | 1,280 | 1.13% |
| Native Hawaiian or Pacific Islander | 20 | 0.02% |
Pennington County 's average per capita income is $47,874. Household income levels show a median of $74,517. The poverty rate stands at 11.16%.
| Name | Median ↓ | Mean |
|---|---|---|
| Married Families | $104,416 | $137,676 |
| Families | $92,479 | $123,622 |
| Households | $74,517 | $99,289 |
| Non Families | $45,577 | $59,084 |
Average Income
Median Household Income
Poverty Rate