Boundary Atlas

ZIP code 57571: St. Charles, SD

ZIP code 57571 is in St. Charles (35% of residents), in Gregory County, South Dakota. 65% of its residents live outside city limits. It is in South Dakota's at-large congressional district. Its state senate district is State Senate District 21; its state house district is State House District 21.

43residents (2020 Census)
10.7 sq miland area
1cities and towns
1congressional district
1voting precincts

See it on the mapAll of South Dakota

City and county

City or townShare of ZIP residents
St. Charles35%

CountyShare of ZIP residents
Gregory County100%

Town or county subdivisionShare of ZIP residents
East Gregory UT100%

Congressional district

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

Members of Congress

OfficeMemberContact
U.S. Representative (SD-AL)Dusty Johnson (R)202-225-2801
U.S. SenatorJohn Thune (R)202-224-2321 · contact form
U.S. SenatorMike Rounds (R)202-224-5842 · contact form

Members serving now (119th Congress, until January 3, 2027). Source: Members of Congress: the @unitedstates project, congress-legislators (CC0).

State legislative districts

State senate districtShare of ZIP residents
State Senate District 21100%

State house districtShare of ZIP residents
State House District 21100%

Voting precincts

1 voting precinct overlap ZIP 57571. Map them, with each precinct's share of the ZIP's residents.

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ZIP 57571 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.