ZIP code 63357 is in Marthasville (21% of residents), in Warren County (95%) and St. Charles County (4.9%), Missouri. 79% of its residents live outside city limits. It is in Missouri's 2nd congressional district. Its state senate districts are State Senate District 26 (95%) and State Senate District 2 (4.9%); its state house districts are State House District 42 (95%) and State House District 102 (4.9%).
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).
11 voting precincts overlap ZIP 63357.
Map them, with each precinct's share of the ZIP's residents.
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related_geographies(id="us:zcta:63357")
ZIP 63357 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.