Boundary Atlas

ZIP code 51023: Hawarden, IA

ZIP code 51023 is in Hawarden (80% of residents), in Sioux County (94%) and Union County (6.5%), Iowa. 20% of its residents live outside city limits. It is in Iowa's 4th congressional district (94%) and South Dakota's at-large congressional district (6.5%). Its state senate districts are State Senate District 2 (94%) and State Senate District 16 (6.5%); its state house districts are State House District 3 (94%) and State House District 16 (6.5%).

3,392residents (2020 Census)
119.9 sq miland area
1cities and towns
2congressional districts
4voting precincts

See it on the mapAll of Iowa

City and county

City or townShare of ZIP residents
Hawarden80%

CountyShare of ZIP residents
Sioux County94%
Union County6.5%

Town or county subdivisionShare of ZIP residents
Buncombe township64%
Logan township20%
Eagle township6.0%
Virginia township5.6%
Garfield township2.1%
Washington township1.4%
Big Springs township0.8%
Alcester township<0.1%

Congressional districts

Congressional districtShare of ZIP residents
Iowa's 4th congressional district (IA-04)94%
South Dakota's at-large congressional district (SD-AL)6.5%

This ZIP is split between districts. A mailing address in it could be in either; the map or locate_point gives the district for an exact address.

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (IA-04)Randy Feenstra (R)202-225-442694%
U.S. Representative (SD-AL)Dusty Johnson (R)202-225-28016.5%
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 2)Jeff Taylor (R)94%
State Senator (State Senate District 16)Kevin Jensen (R)6.5%
State Representative (State House District 3)Tom Jeneary (R)94%
State Representative (State House District 16)John Shubeck (R)6.5%
State Representative (State House District 16)Karla Lems (R)6.5%

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 294%
State Senate District 166.5%

State house districtShare of ZIP residents
State House District 394%
State House District 166.5%

Voting precincts

4 voting precincts overlap ZIP 51023. It also crosses into SD. Map them, with each precinct's share of the ZIP's residents.

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ZIP 51023 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.