Boundary Atlas

ZIP code 53545: Janesville, WI

ZIP code 53545 is in Janesville (90% of residents), in Rock County, Wisconsin. 9.6% of its residents live outside city limits. It is in Wisconsin's 1st congressional district (98%) and Wisconsin's 2nd congressional district (1.6%). Its state senate district is State Senate District 15; its state house districts are Assembly District 44 (98%) and Assembly District 43 (1.6%).

23,318residents (2020 Census)
22.5 sq miland area
1cities and towns
2congressional districts
17voting precincts

See it on the mapAll of Wisconsin

City and county

City or townShare of ZIP residents
Janesville90%

CountyShare of ZIP residents
Rock County100%

Town or county subdivisionShare of ZIP residents
Janesville city90%
Janesville town7.9%
Fulton town1.6%

Congressional districts

Congressional districtShare of ZIP residents
Wisconsin's 1st congressional district (WI-01)98%
Wisconsin's 2nd congressional district (WI-02)1.6%

This ZIP is split between districts. A mailing address in it could be in either; the map or locate_point gives the district for an exact address.

Elected officials

OfficeMemberContactShare of residents
MayorJanesville City Council608-373-601590%
U.S. Representative (WI-01)Bryan Steil (R)202-225-303198%
U.S. Representative (WI-02)Mark Pocan (D)202-225-29061.6%
U.S. SenatorRon Johnson (R)202-224-5323 · contact formstatewide
U.S. SenatorTammy Baldwin (D)202-224-5653 · contact formstatewide
State Senator (State Senate District 15)Mark Spreitzer (Democratic)100%
Assembly Member (Assembly District 44)Ann Roe (Democratic)98%
Assembly Member (Assembly District 43)Brienne Brown (Democratic)1.6%

Officials serving now (members of Congress until January 3, 2027). Sources: Mayors: Open States (public domain); 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 15100%

State house districtShare of ZIP residents
Assembly District 4498%
Assembly District 431.6%

Voting precincts

17 voting precincts overlap ZIP 53545. Map them, with each precinct's share of the ZIP's residents.

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Your agent can get these cities, counties, districts and precincts with their shares, and their GeoJSON boundaries, from Boundary Atlas. Add https://atlas-production-d344.up.railway.app/mcp to Claude, ChatGPT, Cursor or Codex (free, no key; how), then:

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ZIP 53545 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.