ZIP code 51109 is in Sioux City (90% of residents), in Woodbury County (90%) and Plymouth County (10%), Iowa. 10% of its residents live outside city limits. It is in Iowa's 4th congressional district. Its state senate districts are State Senate District 1 (90%) and State Senate District 7 (10%); its state house districts are State House District 1 (90%) and State House District 13 (10%).
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).
2 voting precincts overlap ZIP 51109.
Map them, with each precinct's share of the ZIP's residents.
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ZIP 51109 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.