ZIP code 57426: Oneota, SD
ZIP code 57426 is in Brown County, South Dakota, outside any city or Census-designated place. It is in South Dakota's at-large congressional district. Its state senate district is State Senate District 1; its state house district is State House District 1.
See it on the mapAll of South Dakota
City and county
Outside any city or Census-designated place.
| County | Share of ZIP residents |
|---|---|
| Brown County | 100% |
| Town or county subdivision | Share of ZIP residents |
|---|---|
| Oneota township | 100% |
Congressional district
| Congressional district | Share of ZIP residents |
|---|---|
| South Dakota's at-large congressional district (SD-AL) | 100% |
Elected officials
| Office | Member | Contact | Share of residents |
|---|---|---|---|
| U.S. Representative (SD-AL) | Dusty Johnson (R) | 202-225-2801 | 100% |
| 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 Representative (State House District 1) | Logan Manhart (R) | 100% | |
| State Representative (State House District 1) | Nick Fosness (R) | 100% |
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
- Brown County website: http://www.brown.sd.us
- Brown County laws: search for the Brown County, South Dakota code of ordinances
State legislative districts
| State senate district | Share of ZIP residents |
|---|---|
| State Senate District 1 | 100% |
| State house district | Share of ZIP residents |
|---|---|
| State House District 1 | 100% |
Voting precincts
1 voting precinct overlap ZIP 57426. 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:57426")
ZIP 57426 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.