Boundary Atlas

ZIP code 51565: Portsmouth, IA

ZIP code 51565 is in Portsmouth (39% of residents), in Shelby County (83%) and Harrison County (17%), Iowa. 61% of its residents live outside city limits. It is in Iowa's 4th congressional district. Its state senate districts are State Senate District 6 (83%) and State Senate District 8 (17%); its state house districts are State House District 12 (83%), State House District 15 (17%) and State House District 11 (0.2%).

464residents (2020 Census)
45.7 sq miland area
1cities and towns
1congressional district
4voting precincts

See it on the mapAll of Iowa

City and county

City or townShare of ZIP residents
Portsmouth39%

CountyShare of ZIP residents
Shelby County83%
Harrison County17%

Town or county subdivisionShare of ZIP residents
Cass township83%
Cass township17%
Shelby township0.2%
Douglas townshipland only

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 6)Jason Schultz (R)83%
State Senator (State Senate District 8)Mark Costello (R)17%
State Representative (State House District 12)Steven Holt (R)83%
State Representative (State House District 15)Matt Windschitl (R)17%
State Representative (State House District 11)Craig Williams (R)0.2%

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 683%
State Senate District 817%

State house districtShare of ZIP residents
State House District 1283%
State House District 1517%
State House District 110.2%

Voting precincts

4 voting precincts overlap ZIP 51565. Map them, with each precinct's share of the ZIP's residents.

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ZIP 51565 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.