Union County, South Dakota

Union County, South Dakota, had an estimated population of 17,402 in 2025 across 1,193 km². The figures below come from the US Census Bureau's population estimates and the American Community Survey, each shown with its own vintage and its rank among South Dakota's counties and nationally.

Population: 17,402; 2025 estimate
Area: 1,193 km²
Density: 15; per km²
Median income: $89,636; household, ACS 2024
Median age: 41.5; years, ACS 2024

How South Dakota's counties spread

Amenities & Infrastructure

Indicator	Value	In South Dakota	In the US
Households with Broadband2024	89.5%	18 / 66	945 / 3,144
Median Gross Rent2024	$1,069	5 / 66	785 / 3,137
Median Home Value2024	$301,100	6 / 66	620 / 3,139
Owner-Occupied Homes2024	73.1%	35 / 66	1,820 / 3,144
Vacant Homes2024	3.7%	65 / 66	3,096 / 3,144

Demography

Indicator	Value	In South Dakota	In the US
Aged 65 and Over2024	19.5%	44 / 66	1,713 / 3,144
American Indian & Alaska Native2024	0.7%	49 / 66	570 / 3,144
Asian, non-Hispanic2024	1.1%	12 / 66	931 / 3,144
Average Household Size2024people	2.3	44 / 66	2,238 / 3,144
Black, non-Hispanic2024	0.9%	16 / 66	2,082 / 3,144
Foreign-Born2024	2.0%	25 / 66	1,980 / 3,144
Hispanic or Latino2024	4.8%	18 / 66	1,637 / 3,144
Median Age2024years	41.5	33 / 66	1,565 / 3,144
Sex Ratio2024per 1,000 males	938	48 / 66	2,591 / 3,144
Speak a Language Other Than English2024	3.0%	55 / 66	2,330 / 3,144
Under 182024	24.1%	36 / 66	658 / 3,144
Veterans2024	7.6%	27 / 66	1,292 / 3,144
White, non-Hispanic2024	88.4%	28 / 66	964 / 3,144

Economy

Indicator	Value	In South Dakota	In the US
Below Poverty Line2024	6.2%	60 / 66	3,012 / 3,144
Households on SNAP2024	4.1%	47 / 66	2,981 / 3,144
Income Inequality2024index	0.470	17 / 66	760 / 3,144
Median Household Income2024	$89,636	2 / 66	311 / 3,143
Per Capita Income2024	$53,834	1 / 66	143 / 3,144
Unemployment Rate2024	3.0%	24 / 66	2,463 / 3,144

Education

Indicator	Value	In South Dakota	In the US
Bachelor's Degree or Higher2024	37.0%	5 / 66	371 / 3,144
High School or Higher2024	95.7%	7 / 66	141 / 3,144

Health Coverage

Indicator	Value	In South Dakota	In the US
No Health Insurance2024	5.1%	53 / 66	2,483 / 3,144
With a Disability2024	10.8%	48 / 66	2,909 / 3,144

Population & Density

Indicator	Value	In South Dakota	In the US
Population2025	17,402	13 / 66	1,962 / 3,144
Population Density2025/km²	15	8 / 66	1,673 / 3,144

Work & Commute

Indicator	Value	In South Dakota	In the US
Commute by Public Transit2024	0.0%	32 / 66	2,161 / 3,144
Households with No Vehicle2024	3.7%	41 / 66	2,465 / 3,144
Mean Commute Time2024minutes	17.7	33 / 66	2,791 / 3,143
Work from Home2024	7.9%	47 / 66	1,794 / 3,144

Other counties of South Dakota

Compare Union County against every other county on a map, add layers and run a scatter — open the atlas. Sources and vintages for every figure on this page are listed under datasets, or browse all 3,144 counties.