ZIP code 57430: Britton, SD
ZIP code 57430 is in Britton (57% of residents), Sunset Colony (6.7%) and Kidder (1.2%), in Marshall County (100%) and Sargent County (0.2%), South Dakota. 35% of its residents live outside city limits. It is in South Dakota's at-large congressional district (100%) and North Dakota's at-large congressional district (0.2%). Its state senate districts are State Senate District 1 (100%) and State Senate District 28 (0.2%); its state house districts are State House District 1 (100%) and State House District 28 (0.2%).
See it on the mapAll of South Dakota
City and county
| City or town | Share of ZIP residents |
|---|---|
| Britton | 57% |
| Sunset Colony | 6.7% |
| Kidder | 1.2% |
| Westwood Colony | 0.4% |
| County | Share of ZIP residents |
|---|---|
| Marshall County | 100% |
| Sargent County | 0.2% |
| Town or county subdivision | Share of ZIP residents |
|---|---|
| Britton city | 57% |
| Miller township | 8.3% |
| Stena township | 8.1% |
| Pleasant Valley township | 8.0% |
| White township | 4.9% |
| Waverly township | 3.4% |
| Newark township | 2.6% |
| Lowell township | 2.5% |
| Nordland township | 1.5% |
| Victor township | 1.1% |
| Dayton township | 1.1% |
| Wismer township | 0.7% |
| Hamilton township | 0.4% |
| Brampton township | 0.2% |
| Sisseton township | <0.1% |
Congressional districts
| Congressional district | Share of ZIP residents |
|---|---|
| South Dakota's at-large congressional district (SD-AL) | 100% |
| North Dakota's at-large congressional district (ND-AL) | 0.2% |
This ZIP is split between districts. A mailing address in it could be in either; the map or locate_point gives the district for an exact address.
Elected officials
| Office | Member | Contact | Share of residents |
|---|---|---|---|
| U.S. Representative (SD-AL) | Dusty Johnson (R) | 202-225-2801 | 100% |
| U.S. Representative (ND-AL) | Julie Fedorchak (R) | 202-225-2611 | 0.2% |
| U.S. Senator | John Thune (R) | 202-224-2321 · contact form | statewide |
| U.S. Senator | Mike Rounds (R) | 202-224-5842 · contact form | statewide |
| State Senator (State Senate District 1) | Michael Rohl (R) | 100% | |
| State Senator (State Senate District 28) | Robert Erbele (R) | 0.2% | |
| State Representative (State House District 1) | Logan Manhart (R) | 100% | |
| State Representative (State House District 1) | Nick Fosness (R) | 100% | |
| State Representative (State House District 28) | Jim Grueneich (R) | 0.2% | |
| State Representative (State House District 28) | Mike Brandenburg (R) | 0.2% |
Officials serving now (members of Congress until January 3, 2027). Sources: State legislators: Open States (public domain); Members of Congress: the @unitedstates project, congress-legislators (CC0).
Local government
- Britton website: http://www.brittonsouthdakota.com/
- Britton laws: search for the Britton, South Dakota code of ordinances
- Sunset Colony laws: search for the Sunset Colony, South Dakota code of ordinances
- Kidder laws: search for the Kidder, South Dakota code of ordinances
- Marshall County website: http://marshall.sdcounties.org/
- Marshall County laws: search for the Marshall County, South Dakota code of ordinances
- Sargent County website: http://www.sargentnd.com
- Sargent County laws: search for the Sargent County, South Dakota code of ordinances
State legislative districts
| State senate district | Share of ZIP residents |
|---|---|
| State Senate District 1 | 100% |
| State Senate District 28 | 0.2% |
| State house district | Share of ZIP residents |
|---|---|
| State House District 1 | 100% |
| State House District 28 | 0.2% |
Voting precincts
8 voting precincts overlap ZIP 57430. It also crosses into ND. Map them, with each precinct's share of the ZIP's residents.
Get this in your AI agent
Your agent can get these cities, counties, districts and precincts with their shares, and their GeoJSON boundaries, from Boundary Atlas. Add https://atlas-production-d344.up.railway.app/mcp to Claude, ChatGPT, Cursor or Codex (free, no key; how), then:
related_geographies(id="us:zcta:57430")
ZIP 57430 here is the Census Bureau's ZIP Code Tabulation Area, which approximates the USPS ZIP Code; PO-box-only ZIPs have none. Districts are the maps in force for the November 3, 2026 election.