Boundary Atlas

ZIP code 50647: Janesville, IA

ZIP code 50647 is in Janesville (52% of residents), in Bremer County (70%) and Black Hawk County (30%), Iowa. 48% of its residents live outside city limits. It is in Iowa's 2nd congressional district. Its state senate districts are State Senate District 29 (70%), State Senate District 27 (27%) and State Senate District 34 (3.6%); its state house districts are State House District 57 (70%), State House District 54 (27%) and State House District 68 (3.6%).

1,989residents (2020 Census)
30.4 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
Janesville52%

CountyShare of ZIP residents
Bremer County70%
Black Hawk County30%

Town or county subdivisionShare of ZIP residents
Jackson township68%
Washington township16%
Union township11%
Mount Vernon township3.6%
Jefferson township1.7%

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 29)Sandy Salmon (R)70%
State Senator (State Senate District 27)Annette Sweeney (R)27%
State Senator (State Senate District 34)Dan Zumbach (R)3.6%
State Representative (State House District 57)Pat Grassley (R)70%
State Representative (State House District 54)Josh Meggers (R)27%
State Representative (State House District 68)Chad Ingels (R)3.6%

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 2970%
State Senate District 2727%
State Senate District 343.6%

State house districtShare of ZIP residents
State House District 5770%
State House District 5427%
State House District 683.6%

Voting precincts

4 voting precincts overlap ZIP 50647. Map them, with each precinct's share of the ZIP's residents.

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ZIP 50647 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.