Counties in South Dakota by uninsured rate, ages 18 to 64 (US model-based estimate)
Buffalo County had the highest uninsured rate, ages 18 to 64 (US model-based estimate) of 66 counties in 2018, at 28.5%. Lincoln County had the lowest, at 7.9%. The median was 13.3% and the figure for South Dakota was 13.6%. Source: the U.S. Census Bureau.
Map of counties, 2018
- Under 12
- 12 to 13
- 13 to 16
- 16 to 21
- 21 and over
Top 40 counties, 2018
Full ranking
| Rank | Counties | 2018 (%) | Change on 2017 |
|---|---|---|---|
| 1 | Buffalo County | 28.5 | +1.1 pts |
| 2 | Jackson County | 28.4 | -2.7 pts |
| 3 | Corson County | 28.3 | -0.1 pts |
| 4 | Todd County | 28.1 | +2.6 pts |
| 5 | Bennett County | 27.3 | -1.2 pts |
| 6 | Ziebach County | 26.5 | -1.7 pts |
| 7 | Dewey County | 26 | -0.9 pts |
| 8 | Mellette County | 25.6 | -3.4 pts |
| 9 | Oglala Lakota County | 24.4 | +0.4 pts |
| 10 | Charles Mix County | 21.3 | +0.2 pts |
| 10 | Roberts County | 21.3 | -1.3 pts |
| 12 | Lyman County | 20.5 | -2.1 pts |
| 13 | Tripp County | 20 | -0.2 pts |
| 14 | Gregory County | 19 | +2 pts |
| 15 | Brule County | 18.9 | -0.9 pts |
| 16 | Beadle County | 18.7 | +2.1 pts |
| 17 | Marshall County | 18.2 | -0.6 pts |
| 18 | Aurora County | 17.6 | +0.8 pts |
| 19 | Moody County | 17.4 | +0.1 pts |
| 20 | Walworth County | 16.5 | +0.6 pts |
| 21 | Douglas County | 16.3 | +2.1 pts |
| 22 | Day County | 16.1 | +0.5 pts |
| 23 | Butte County | 16 | +2.5 pts |
| 23 | Pennington County | 16 | +2 pts |
| 25 | Perkins County | 15.8 | -0.8 pts |
| 26 | Clark County | 15.1 | -1 pts |
| 27 | Hutchinson County | 14.4 | +0.9 pts |
| 28 | Jones County | 14.2 | -3.2 pts |
| 29 | McCook County | 14.1 | +2.1 pts |
| 30 | Hyde County | 13.9 | +0.7 pts |
| 31 | McPherson County | 13.7 | -0.9 pts |
| 32 | Custer County | 13.5 | +0.6 pts |
| 33 | Jerauld County | 13.3 | +1 pts |
| 34 | Harding County | 13.2 | -1 pts |
| 35 | Bon Homme County | 13.1 | +0.9 pts |
| 35 | Grant County | 13.1 | +1.2 pts |
| 37 | Faulk County | 13 | +2.2 pts |
| 38 | Fall River County | 12.9 | +0.4 pts |
| 39 | Brown County | 12.7 | +0.2 pts |
| 39 | Hanson County | 12.7 | 0 pts |
| 39 | Lawrence County | 12.7 | +1.3 pts |
| 42 | Hughes County | 12.4 | +1.1 pts |
| 43 | Sanborn County | 12.2 | -1.8 pts |
| 43 | Spink County | 12.2 | +0.1 pts |
| 45 | Minnehaha County | 12.1 | +1.7 pts |
| 45 | Yankton County | 12.1 | +1.1 pts |
| 47 | Deuel County | 12 | +1.3 pts |
| 47 | Sully County | 12 | -1.3 pts |
| 49 | Haakon County | 11.9 | -1.5 pts |
| 49 | Hamlin County | 11.9 | -0.7 pts |
| 49 | Hand County | 11.9 | +0.5 pts |
| 52 | Davison County | 11.8 | +1.9 pts |
| 52 | Edmunds County | 11.8 | -0.4 pts |
| 52 | Turner County | 11.8 | +0.7 pts |
| 55 | Miner County | 11.7 | +0.8 pts |
| 55 | Stanley County | 11.7 | -0.2 pts |
| 57 | Clay County | 11.6 | -0.3 pts |
| 58 | Kingsbury County | 11.2 | +0.4 pts |
| 58 | Meade County | 11.2 | -0.8 pts |
| 60 | Campbell County | 11.1 | -0.6 pts |
| 60 | Potter County | 11.1 | -1.3 pts |
| 62 | Codington County | 10.9 | +0.6 pts |
| 63 | Brookings County | 10.8 | +0.4 pts |
| 64 | Lake County | 10.1 | +1.4 pts |
| 65 | Union County | 8 | -0.8 pts |
| 66 | Lincoln County | 7.9 | +0.6 pts |
Other periods
About this ranking
People aged 18 to 64 without health insurance coverage of any kind, as a percentage of all people aged 18 to 64. United States: Census Bureau Small Area Health Insurance Estimates (SAHIE) for states and counties, all races, both sexes and all income levels.
A model-based single-year estimate that combines the American Community Survey with administrative records and population estimates, so every county gets a figure. Covers states and counties only, because the SAHIE dataset files have no national row. The Census Bureau advises comparing years from 2008 on only; 2013 is the updated release. Working-age adults; the rate for everyone under 65 is uninsured_rate_under_65.
Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. Equal values share a rank.
How to cite
U.S. Census Bureau. Small Area Health Insurance Estimates (SAHIE): percent uninsured, ages 18 to 64, all races, both sexes, all income levels, states and counties. https://www2.census.gov/programs-surveys/sahie/datasets/time-series/estimates-acs/sahie-2018-csv.zip. Retrieved 2026-10-12.
Citation styles
APA 7
U.S. Census Bureau. (2026). Small Area Health Insurance Estimates (SAHIE): percent uninsured, ages 18 to 64, all races, both sexes, all income levels, states and counties (Counties in South Dakota by uninsured rate, ages 18 to 64 (US model-based estimate), 2018) [Data set]. Retrieved October 12, 2026, from https://www2.census.gov/programs-surveys/sahie/datasets/time-series/estimates-acs/sahie-2018-csv.zip
MLA 9
Small Area Health Insurance Estimates (SAHIE): percent uninsured, ages 18 to 64, all races, both sexes, all income levels, states and counties, Counties in South Dakota by uninsured rate, ages 18 to 64 (US model-based estimate), 2018. U.S. Census Bureau, 6 Aug. 2026, https://www2.census.gov/programs-surveys/sahie/datasets/time-series/estimates-acs/sahie-2018-csv.zip. Invokely, https://invokely.ai/rankings/uninsured-rate-ages-18-64/south-dakota-counties?period=2018. Accessed 12 Oct. 2026.
Chicago (author-date)
U.S. Census Bureau. 2026. Small Area Health Insurance Estimates (SAHIE): percent uninsured, ages 18 to 64, all races, both sexes, all income levels, states and counties. Counties in South Dakota by uninsured rate, ages 18 to 64 (US model-based estimate), 2018. Dataset. Accessed October 12, 2026. https://www2.census.gov/programs-surveys/sahie/datasets/time-series/estimates-acs/sahie-2018-csv.zip. Also distributed by Invokely, https://invokely.ai/rankings/uninsured-rate-ages-18-64/south-dakota-counties?period=2018.
Harvard
U.S. Census Bureau (2026) Small Area Health Insurance Estimates (SAHIE): percent uninsured, ages 18 to 64, all races, both sexes, all income levels, states and counties, Counties in South Dakota by uninsured rate, ages 18 to 64 (US model-based estimate), 2018 [Dataset]. Available at: https://www2.census.gov/programs-surveys/sahie/datasets/time-series/estimates-acs/sahie-2018-csv.zip, via Invokely: https://invokely.ai/rankings/uninsured-rate-ages-18-64/south-dakota-counties?period=2018 (Accessed: 12 October 2026).
BibTeX
@misc{census_counties_in_south_dakota_2018,
author = {{U.S. Census Bureau}},
title = {{Small Area Health Insurance Estimates (SAHIE): percent uninsured, ages 18 to 64, all races, both sexes, all income levels, states and counties: Counties in South Dakota by uninsured rate, ages 18 to 64 (US model-based estimate), 2018}},
year = {2026},
howpublished = {Data set},
url = {https://www2.census.gov/programs-surveys/sahie/datasets/time-series/estimates-acs/sahie-2018-csv.zip},
urldate = {2026-10-12},
note = {Accessed via Invokely, https://invokely.ai/rankings/uninsured-rate-ages-18-64/south-dakota-counties?period=2018. Publisher attribution: U.S. Census Bureau. Small Area Health Insurance Estimates (SAHIE): percent uninsured, ages 18 to 64, all races, both sexes, all income levels, states and counties. https://www2.census.gov/programs-surveys/sahie/datasets/time-series/estimates-acs/sahie-2018-csv.zip. Retrieved 2026-10-12.},
}
RIS
TY - DATA
AU - U.S. Census Bureau
TI - Small Area Health Insurance Estimates (SAHIE): percent uninsured, ages 18 to 64, all races, both sexes, all income levels, states and counties: Counties in South Dakota by uninsured rate, ages 18 to 64 (US model-based estimate), 2018
PY - 2026
DA - 2026/08/06
PB - U.S. Census Bureau
DB - Invokely
UR - https://www2.census.gov/programs-surveys/sahie/datasets/time-series/estimates-acs/sahie-2018-csv.zip
L2 - https://invokely.ai/rankings/uninsured-rate-ages-18-64/south-dakota-counties?period=2018
Y2 - 2026/10/12
N1 - Accessed via Invokely, https://invokely.ai/rankings/uninsured-rate-ages-18-64/south-dakota-counties?period=2018.
N1 - Publisher attribution: U.S. Census Bureau. Small Area Health Insurance Estimates (SAHIE): percent uninsured, ages 18 to 64, all races, both sexes, all income levels, states and counties. https://www2.census.gov/programs-surveys/sahie/datasets/time-series/estimates-acs/sahie-2018-csv.zip. Retrieved 2026-10-12.
ER -
Use this data in your AI agent
Invokely serves this figure to AI assistants through MCP and to code through a REST API, with the source and citation attached. Ask your assistant:
Rank Counties in South Dakota by uninsured rate, ages 18 to 64 (US model-based estimate) using official data, and cite the source.
rank_places {"indicator":"uninsured_rate_18_64","level":"province","within":"South Dakota","limit":10}
GET https://invokely.ai/api/v1/rank?indicator=uninsured_rate_18_64&level=province&within=South%20Dakota&limit=10
Questions
Which county has the highest uninsured rate, ages 18 to 64 (US model-based estimate)?
Buffalo County, with 28.5% in 2018, according to the U.S. Census Bureau.
Which county has the lowest uninsured rate, ages 18 to 64 (US model-based estimate)?
Lincoln County, with 7.9% in 2018.
Where does this ranking come from?
Every value comes from one source and one period, so the places are comparable: U.S. Census Bureau, Small Area Health Insurance Estimates (SAHIE): percent uninsured, ages 18 to 64, all races, both sexes, all income levels, states and counties. Retrieved 2026-10-12.
Uninsured rate, ages 18 to 64 (US model-based estimate): other rankings
Counties in South Dakota: more rankings
- Adult obesity rate, local model estimate
- COPD in adults, local model estimate
- Binge drinking in adults, local model estimate
- Uninsured rate, under 19 (US model-based estimate)
- Net domestic migration, July to June
- Population
- Poverty rate (US five-year survey estimate)
- High school graduate or higher, population 25 and over