Boundary Atlas

ZIP code 54421: Colby, WI

ZIP code 54421 is in Colby (53% of residents), in Clark County (58%) and Marathon County (42%), Wisconsin. 47% of its residents live outside city limits. It is in Wisconsin's 7th congressional district. Its state senate district is State Senate District 23; its state house district is Assembly District 69.

3,651residents (2020 Census)
69.9 sq miland area
2cities and towns
1congressional district
10voting precincts

See it on the mapAll of Wisconsin

City and county

City or townShare of ZIP residents
Colby53%
Abbotsford0.4%

CountyShare of ZIP residents
Clark County58%
Marathon County42%

Town or county subdivisionShare of ZIP residents
Colby city35%
Colby town23%
Colby city19%
Hull town18%
Frankfort town5.3%
Green Grove town0.5%
Abbotsford city0.4%

Congressional district

Congressional districtShare of ZIP residents
Wisconsin's 7th congressional district (WI-07)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (WI-07)Thomas P. Tiffany (R)202-225-3365100%
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 23)Jesse James (R)100%
Assembly Member (Assembly District 69)Karen Hurd (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 23100%

State house districtShare of ZIP residents
Assembly District 69100%

Voting precincts

10 voting precincts overlap ZIP 54421. Map them, with each precinct's share of the ZIP's residents.

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ZIP 54421 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.