ZIP CodesZIP codes in Union County, South Dakota
Union County, South Dakota has 5 ZIP codes in this list, from 57001 to 57049. They cover 5 places, among them Alcester, Beresford, Elk Point and Jefferson.
| ZIP code | Place | Land area (sq mi) | Map point |
|---|---|---|---|
| 57001 | Alcester | 99.3 | 43.005, -96.633 |
| 57004 | Beresford | 195 | 43.087, -96.781 |
| 57025 | Elk Point | 124 | 42.738, -96.687 |
| 57038 | Jefferson | 50.6 | 42.601, -96.578 |
| 57049 | North Sioux City | 14.2 | 42.525, -96.507 |
The ZIP code areas of Union County add up to about 483 square miles of land (1,250 sq km) as the Census Bureau draws them. The largest is 57004 (Beresford), with 195 square miles.
Using these codes
- In an address, the ZIP code comes last, after the city and the two-letter state: Alcester, SD 57001.
- Tap a ZIP code to open it in the look-up, with a copy button for the address line.
- A code can cross a county line, and one town can have several codes. The table shows the main place of each code.
- "No area" means the Census Bureau draws no area for that code. Such codes are usually for post office boxes or a single building.
Places and counties: GeoNames. Areas: U.S. Census Bureau, 2024 ZIP Code Tabulation Areas. Checked in November 2026. This site is not connected with the United States Postal Service; for mailing, confirm the address with USPS.