ZIP CodesZIP codes in Buffalo County, South Dakota
Buffalo County, South Dakota has 2 ZIP codes in this list, from 57339 to 57341. They cover 2 places, among them Fort Thompson and Gann Valley.
| ZIP code | Place | Land area (sq mi) | Map point |
|---|---|---|---|
| 57339 | Fort Thompson | 54.2 | 44.052, -99.397 |
| 57341 | Gann Valley | 248 | 44.069, -99.054 |
The ZIP code areas of Buffalo County add up to about 302 square miles of land (783 sq km) as the Census Bureau draws them. The largest is 57341 (Gann Valley), with 248 square miles.
Using these codes
- In an address, the ZIP code comes last, after the city and the two-letter state: Fort Thompson, SD 57339.
- 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.