Boundary Atlas

ZIP code 50401: Mason City, IA

ZIP code 50401 is in Mason City (94% of residents), in Cerro Gordo County, Iowa. 5.7% of its residents live outside city limits. It is in Iowa's 2nd congressional district. Its state senate district is State Senate District 30; its state house districts are State House District 59 (99%) and State House District 60 (0.9%).

28,981residents (2020 Census)
148.2 sq miland area
3cities and towns
1congressional district
16voting precincts

See it on the mapAll of Iowa

City and county

City or townShare of ZIP residents
Mason City94%
Rock Falls0.2%
Portland<0.1%

CountyShare of ZIP residents
Cerro Gordo County100%

Town or county subdivisionShare of ZIP residents
Mason City city94%
Lime Creek township1.6%
Mason township1.2%
Falls township0.9%
Bath township0.5%
Lake township0.5%
Portland township0.4%
Lincoln township0.3%
Owen township0.2%

Congressional district

Congressional districtShare of ZIP residents
Iowa's 2nd congressional district (IA-02)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (IA-02)Ashley Hinson (R)202-225-2911100%
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 30)Doug Campbell (R)100%
State Representative (State House District 59)Christian Hermanson (R)99%
State Representative (State House District 60)Jane Bloomingdale (R)0.9%

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 30100%

State house districtShare of ZIP residents
State House District 5999%
State House District 600.9%

Voting precincts

16 voting precincts overlap ZIP 50401. Map them, with each precinct's share of the ZIP's residents.

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ZIP 50401 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.