ZIP code 57730 is in Custer (37% of residents), in Custer County (98%) and Pennington County (1.6%), South Dakota. 63% 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 30; its state house district is State House District 30.
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).
10 voting precincts overlap ZIP 57730.
Map them, with each precinct's share of the ZIP's residents.
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related_geographies(id="us:zcta:57730")
ZIP 57730 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.