Boundary Atlas

ZIP code 51111: Sioux City, IA

ZIP code 51111 is in Sioux City, in Woodbury County, Iowa. It is in Iowa's 4th congressional district. Its state senate district is State Senate District 7; its state house district is State House District 14.

97residents (2020 Census)
6.1 sq miland area
1cities and towns
1congressional district
1voting precincts

See it on the mapAll of Iowa

City and county

City or townShare of ZIP residents
Sioux City100%

CountyShare of ZIP residents
Woodbury County100%

Town or county subdivisionShare of ZIP residents
Sioux City city100%

Congressional district

Congressional districtShare of ZIP residents
Iowa's 4th congressional district (IA-04)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (IA-04)Randy Feenstra (R)202-225-4426100%
U.S. SenatorChuck Grassley (R)202-224-3744 · contact formstatewide
U.S. SenatorJoni Ernst (R)202-224-3254 · contact formstatewide
State Senator (State Senate District 7)Kevin Alons (R)100%
State Representative (State House District 14)Jacob Bossman (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 7100%

State house districtShare of ZIP residents
State House District 14100%

Voting precincts

1 voting precinct overlap ZIP 51111. Map them, with each precinct's share of the ZIP's residents.

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ZIP 51111 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.