Boundary Atlas

ZIP code 57223: Castlewood, SD

ZIP code 57223 is in Castlewood (49% of residents), Claremont Colony (4.7%) and Lake Poinsett (2.3%), in Hamlin County (99%) and Deuel County (0.6%), South Dakota. 44% 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 4; its state house district is State House District 4.

1,437residents (2020 Census)
124.6 sq miland area
4cities and towns
1congressional district
4voting precincts

See it on the mapAll of South Dakota

City and county

City or townShare of ZIP residents
Castlewood49%
Claremont Colony4.7%
Lake Poinsett2.3%
Poinsett Colony0.4%

CountyShare of ZIP residents
Hamlin County99%
Deuel County0.6%

Town or county subdivisionShare of ZIP residents
Castlewood city49%
Castlewood township13%
Dempster township13%
Hamlin township12%
Florence township8.8%
Estelline township3.1%
Oxford township0.7%
Hidewood township0.6%

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 4)Stephanie Sauder (R)100%
State Representative (State House District 4)Dylan Jordan (R)100%
State Representative (State House District 4)Kent Roe (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 4100%

State house districtShare of ZIP residents
State House District 4100%

Voting precincts

4 voting precincts overlap ZIP 57223. Map them, with each precinct's share of the ZIP's residents.

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ZIP 57223 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.