Boundary Atlas

ZIP code 57042: Madison, SD

ZIP code 57042 is in Madison (76% of residents), Lake Madison (3.9%) and Rustic Acres Colony (1.6%), in Lake County (100%) and McCook County (0.1%), South Dakota. 18% of its residents live outside city limits. It is in South Dakota's at-large congressional district. Its state senate districts are State Senate District 8 (100%) and State Senate District 19 (0.1%); its state house districts are State House District 8 (100%) and State House District 19 (0.1%).

8,131residents (2020 Census)
193.2 sq miland area
3cities and towns
1congressional district
10voting precincts

See it on the mapAll of South Dakota

City and county

City or townShare of ZIP residents
Madison76%
Lake Madison3.9%
Rustic Acres Colony1.6%

CountyShare of ZIP residents
Lake County100%
McCook County0.1%

Town or county subdivisionShare of ZIP residents
Madison city76%
Herman township8.2%
Lake View township6.7%
Franklin township3.1%
Farmington township2.4%
Le Roy township1.6%
Orland township1.0%
Concord township0.3%
Winfred township0.2%
Nunda township0.2%
Ramsey township0.1%
Clarno township<0.1%

Congressional district

Congressional districtShare of ZIP residents
South Dakota's at-large congressional district (SD-AL)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (SD-AL)Dusty Johnson (R)202-225-2801100%
U.S. SenatorJohn Thune (R)202-224-2321 · contact formstatewide
U.S. SenatorMike Rounds (R)202-224-5842 · contact formstatewide
State Senator (State Senate District 8)Casey Crabtree (R)100%
State Senator (State Senate District 19)Kyle Schoenfish (R)0.1%
State Representative (State House District 8)Tim Reisch (R)100%
State Representative (State House District 8)Tim Walburg (R)100%
State Representative (State House District 19)Drew Peterson (R)0.1%
State Representative (State House District 19)Jessica Bahmuller (R)0.1%

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

State legislative districts

State senate districtShare of ZIP residents
State Senate District 8100%
State Senate District 190.1%

State house districtShare of ZIP residents
State House District 8100%
State House District 190.1%

Voting precincts

10 voting precincts overlap ZIP 57042. Map them, with each precinct's share of the ZIP's residents.

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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:57042")

ZIP 57042 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.