Market insights · South Dakota
Union County, SD: growth, migration and housing
Union County has 17,402 residents, up 3.3% since 2020 (+0.2% in the last year). In 2022–2023, 607 households moved in and 629 moved out (-22 net), while a net $15.1M of income left. Median household income is $89,636, the median home $301,100 and median rent $1,069 a month.
In South Dakota: 18th of 66 counties for 5-year population growth · 25th of 62 counties for net in-migration (per resident) · 2nd of 66 counties for median household income · 6th of 66 counties for median home value.
Where new residents came from
Top counties by households (tax returns) moving to Union County, 2022–2023 (IRS).
| From | Households (tax returns) | Their income (AGI) |
|---|---|---|
| Woodbury County, IA | 177 | $11.1M |
| Minnehaha County, SD | 42 | $2.5M |
| Lincoln County, SD | 41 | $3.7M |
| Clay County, SD | 27 | $1.5M |
| Dakota County, NE | 26 | $1.9M |
Where leavers went
Top counties by households leaving Union County, 2022–2023 (IRS).
| To | Households (tax returns) | Their income (AGI) |
|---|---|---|
| Woodbury County, IA | 134 | $7.8M |
| Lincoln County, SD | 71 | $8.2M |
| Minnehaha County, SD | 62 | $4.6M |
| Clay County, SD | 31 | $2.5M |
| Washington County, AR | 30 | $7.6M |
| Benton County, AR | 20 | $5.4M |
BizyFi in Union County
No companies in the BizyFi directory are based here yet. Search them on the company map (company names with a free account), or browse South Dakota companies.
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Sources: U.S. Census Bureau population estimates (vintage 2025), American Community Survey 5-year (2024), and IRS Statistics of Income county-to-county migration data (2022–2023). Migration counts are tax returns (roughly households) moving between U.S. counties; the IRS suppresses very small flows. Growth rates, per-1,000 figures, rent share and state ranks are BizyFi calculations. Data updated 2026-10-17. This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.