# Counties in South Dakota by population aged 18 to 64, 2025

All 66 values come from U.S. Census Bureau for 2025, so the places are comparable.

- Indicator id: `population_18_64_share`
- Unit: %
- Definition: Residents aged 18 to 64 as a percentage of total population on 1 July. United States: Census Bureau county population estimates by age; states and the nation are sums of their counties.
- Source: U.S. Census Bureau, Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties (https://www.census.gov/programs-surveys/popest/data/data-sets.html)
- Retrieved: 2026-10-12
- Citation: U.S. Census Bureau. Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Retrieved 2026-10-12.
- Web page: https://invokely.ai/rankings/population-18-64/south-dakota-counties

| Rank | Place | % |
|---:|---|---:|
| 1 | Clay County | 69.6 |
| 2 | Brookings County | 64.2 |
| 3 | Minnehaha County | 60.2 |
| 4 | Lincoln County | 59.8 |
| 5 | Meade County | 59.7 |
| 6 | Pennington County | 58.1 |
| 7 | Bon Homme County | 57.9 |
| 8 | Lawrence County | 57.2 |
| 9 | Brown County | 57.1 |
| 10 | Hughes County | 57.1 |
| 11 | Codington County | 57 |
| 12 | Oglala Lakota County | 57 |
| 13 | Ziebach County | 56.7 |
| 14 | Davison County | 56.4 |
| 15 | Sully County | 56 |
| 16 | Yankton County | 55.8 |
| 17 | Lake County | 55.5 |
| 18 | Union County | 55.3 |
| 19 | Todd County | 54.8 |
| 20 | Lyman County | 54.7 |
| 21 | Stanley County | 54.2 |
| 22 | Hanson County | 54 |
| 23 | Edmunds County | 53.4 |
| 24 | Aurora County | 53.3 |
| 25 | Bennett County | 53 |
| 26 | Butte County | 52.9 |
| 27 | Beadle County | 52.9 |
| 28 | Buffalo County | 52.5 |
| 29 | Charles Mix County | 52.4 |
| 30 | Spink County | 52.3 |
| 31 | Deuel County | 52 |
| 32 | Sanborn County | 52 |
| 33 | Turner County | 52 |
| 34 | Harding County | 51.8 |
| 35 | Jackson County | 51.7 |
| 36 | Moody County | 51.6 |
| 37 | Corson County | 51.5 |
| 38 | Walworth County | 51.4 |
| 39 | Brule County | 51.2 |
| 40 | McCook County | 51.1 |
| 41 | Grant County | 51 |
| 42 | Hamlin County | 51 |
| 43 | Tripp County | 50.9 |
| 44 | Miner County | 50.6 |
| 45 | Marshall County | 50.3 |
| 46 | Hutchinson County | 50.1 |
| 47 | Dewey County | 50 |
| 48 | Clark County | 49.9 |
| 49 | Day County | 49.7 |
| 50 | Roberts County | 49.6 |
| 51 | Kingsbury County | 49.6 |
| 52 | Hyde County | 49.5 |
| 53 | Hand County | 49.2 |
| 54 | Fall River County | 48.8 |
| 55 | Jones County | 48.7 |
| 56 | McPherson County | 48.6 |
| 57 | Perkins County | 48.5 |
| 58 | Haakon County | 48.4 |
| 59 | Faulk County | 48.3 |
| 60 | Campbell County | 48.3 |
| 61 | Custer County | 47.7 |
| 62 | Gregory County | 47.4 |
| 63 | Douglas County | 46.5 |
| 64 | Potter County | 45.5 |
| 65 | Mellette County | 44.4 |
| 66 | Jerauld County | 42.6 |