Boundary Atlas

ZIP code 52309: Monmouth, IA

ZIP code 52309 is in Monmouth (31% of residents), in Jackson County (78%) and Jones County (22%), Iowa. 69% of its residents live outside city limits. It is in Iowa's 1st congressional district. Its state senate districts are State Senate District 35 (55%) and State Senate District 33 (45%); its state house districts are State House District 70 (55%) and State House District 66 (45%).

419residents (2020 Census)
34.3 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
Monmouth31%

CountyShare of ZIP residents
Jackson County78%
Jones County22%

Town or county subdivisionShare of ZIP residents
Monmouth township55%
Brandon township23%
Wyoming township12%
Clay township10%

Congressional district

Congressional districtShare of ZIP residents
Iowa's 1st congressional district (IA-01)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (IA-01)Mariannette Miller-Meeks (R)202-225-6576100%
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 35)Mike Zimmer (Democratic)55%
State Senator (State Senate District 33)Carrie Koelker (R)45%
State Representative (State House District 70)Norlin Mommsen (R)55%
State Representative (State House District 66)Steve Bradley (R)45%

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 3555%
State Senate District 3345%

State house districtShare of ZIP residents
State House District 7055%
State House District 6645%

Voting precincts

4 voting precincts overlap ZIP 52309. Map them, with each precinct's share of the ZIP's residents.

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ZIP 52309 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.