Boundary Atlas

ZIP code 51355: Okoboji, IA

ZIP code 51355 is in Okoboji (91% of residents), in Dickinson County, Iowa. 9.3% of its residents live outside city limits. It is in Iowa's 4th congressional district. Its state senate district is State Senate District 5; its state house district is State House District 10.

847residents (2020 Census)
2.5 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
Okoboji91%

CountyShare of ZIP residents
Dickinson County100%

Town or county subdivisionShare of ZIP residents
Center Grove township93%
Lakeville township6.7%

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 5)Dave Rowley (R)100%
State Representative (State House District 10)John Wills (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 5100%

State house districtShare of ZIP residents
State House District 10100%

Voting precincts

1 voting precinct overlap ZIP 51355. Map them, with each precinct's share of the ZIP's residents.

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ZIP 51355 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.