Boundary Atlas

ZIP code 57078: Yankton, SD

ZIP code 57078 is in Yankton (77% of residents), in Yankton County, South Dakota. 23% 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 18; its state house district is State House District 18.

20,104residents (2020 Census)
111.3 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
Yankton77%

CountyShare of ZIP residents
Yankton County100%

Town or county subdivisionShare of ZIP residents
Yankton city77%
West Yankton UT15%
Southeast Yankton UT3.8%
Utica township3.5%
Mission Hill township0.9%
Walshtown 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 18)Lauren Nelson (R)100%
State Representative (State House District 18)Julie Auch (R)100%
State Representative (State House District 18)Mike Stevens (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

State legislative districts

State senate districtShare of ZIP residents
State Senate District 18100%

State house districtShare of ZIP residents
State House District 18100%

Voting precincts

1 voting precinct overlap ZIP 57078. Map them, with each precinct's share of the ZIP's residents.

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ZIP 57078 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.