Union County's estimated 2026 population is 17,431 with a growth rate of 0.17% in the past year according to the most recent United States census data. Union County is the 13th largest county in South Dakota. The 2010 population was 14,488 and has seen a growth of 20.31% since that time.
Data after 2023 is projected based on recent change
Overall: 41.5 years
Female: 42.8 years
Male: 39.7 years
There are 12,973 adults, (3,328 of whom are seniors) in Union County.
Female: 8,269 (48.4%)
Male: 8,812 (51.6%)
The racial composition of Union County includes 89.97% White, and smaller percentages for Asian, Native American, Black or African American, other race, Native Hawaiian or Pacific Islander and multiracial populations.
Race | Population | Percentage (of total) |
|---|---|---|
| White | 15,367 | 89.97% |
| Two or more races | 1,054 | 6.17% |
| Asian | 190 | 1.11% |
| Native American | 167 | 0.98% |
| Black or African American | 160 | 0.94% |
| Other race | 125 | 0.73% |
| Native Hawaiian or Pacific Islander | 18 | 0.11% |
Union County's average per capita income is $59,260. Household income levels show a median of $89,636. The poverty rate stands at 6.21%.
Name | Median | Mean |
|---|---|---|
| Married Families | $118,022 | - |
| Families | $109,958 | $153,155 |
| Households | $89,636 | $124,814 |
| Non Families | $46,990 | $59,606 |
Average Income
Median Household Income
Poverty Rate