Dewey County, SD ZIP codes
There are 7 ZIP codes in Dewey County, SD, in 7 towns, from 57601 to 57661. The largest are 57601 (Mobridge), 57625 (Eagle Butte) and 57656 (Timber Lake). 1 more crosses into it from a neighbouring county: 57633.
The county seat is Timber Lake.
- ZIP codes
- 7
- Partly in it
- 1 more
- Towns
- 7
- County seat
- Timber Lake
- County FIPS
46041- State
- South Dakota
- Population
- 5,205
- Median household income
- $54,104
- Land area
- 2,302 sq mi
Dewey County ZIP codes by town
- Timber Lake (county seat)
- 57656
Each ZIP code is listed under the county most of its land lies in and the town the Postal Service names it for; a ZIP code's own page shows exactly how it is split.
ZIP codes partly in Dewey County
This ZIP code lies mostly in a neighbouring county but covers a twentieth or more of Dewey County.
- 57633 Isabel · mostly in Corson County
Map of Dewey County ZIP codes
The ZIP codes of Dewey County, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.
Dewey County in numbers
About 5,205 people live in Dewey County, in 1,692 households, the 36th most populous of South Dakota's 66 counties. The median household income is $54,104 a year, 28% below the South Dakota median of $75,081 (US: $80,734). The median owner-occupied home is valued at $69,600 (73% below the South Dakota median), and median gross rent is $692 a month. The median age is 27.7; 18.8% of adults 25 and over hold a bachelor's degree or higher (31.9% across South Dakota); the average commute takes 19 minutes.
| Population | 5,205 |
|---|---|
| Households | 1,692 |
| Median age | 27.7 |
| Median household income | $54,104 |
| Median home value | $69,600 |
| Median gross rent | $692 |
| Bachelor's degree or higher | 18.8% |
| Mean commute | 18.5 min |
| Population density | 2 / sq mi |
U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates. Survey estimates carry margins of error, wider for small places. Sources and methods.
Largest towns in Dewey County
| Town | ZIP codes | Population |
|---|---|---|
| Mobridge | 1 | 2,932 |
| Eagle Butte | 1 | 1,458 |
| Timber Lake | 1 | 779 |
| Ridgeview | 1 | 265 |
| Whitehorse | 1 | 162 |
| Glencross | 1 | 11 |
| Lantry | 1 | 3 |
Population of the census place of that name where there is one, otherwise of the ZIP codes the Postal Service addresses by it. A town's ZIP codes can reach past the county line.
Neighbouring counties
Counties that share a ZIP code with Dewey County.
Not sure you are in Dewey County? What county am I in? answers from your location, near a county line included.
Every ZIP code in Dewey County, with figures
| ZIP | City | Type | Population | Median income | Median home |
|---|---|---|---|---|---|
57601 | Mobridge , SD | Standard | 3,422 | $66,003 | $154,600 |
57625 | Eagle Butte , SD | Standard | 3,775 | $43,235 | $68,000 |
57630 | Glencross , SD | Standard | 11 | — | — |
57636 | Lantry , SD | Standard | 104 | $112,375 | $108,800 |
57652 | Ridgeview , SD | Standard | 265 | $19,327 | — |
57656 | Timber Lake , SD | Standard | 1,000 | $66,094 | $86,300 |
57661 | Whitehorse , SD | Standard | 177 | $55,000 | — |
Cite this page
zipcodes.pro. “Dewey County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/sd/county/dewey
Underlying data is public domain or openly licensed — sources, vintages and licences.