Boundary Atlas

ZIP code 53066: Oconomowoc, WI

ZIP code 53066 is in Oconomowoc (50% of residents), Summit (13%), Okauchee Lake (11%), Ashippun (2.4%) and Oconomowoc Lake (1.6%), in Waukesha County (90%), Jefferson County (5.5%) and Dodge County (4.1%), Wisconsin. 22% of its residents live outside city limits. It is in Wisconsin's 5th congressional district. Its state senate district is State Senate District 33; its state house districts are Assembly District 99 (82%) and Assembly District 97 (18%).

36,595residents (2020 Census)
103.2 sq miland area
7cities and towns
1congressional district
45voting precincts

See it on the mapAll of Wisconsin

City and county

City or townShare of ZIP residents
Oconomowoc50%
Summit13%
Okauchee Lake11%
Ashippun2.4%
Oconomowoc Lake1.6%
Lac La Belle0.9%
Dousman0.1%

CountyShare of ZIP residents
Waukesha County90%
Jefferson County5.5%
Dodge County4.1%

Town or county subdivisionShare of ZIP residents
Oconomowoc city50%
Oconomowoc town21%
Summit village13%
Ashippun town4.1%
Ixonia town3.6%
Merton town2.5%
Concord town1.8%
Oconomowoc Lake village1.6%
Ottawa town0.9%
Lac La Belle village0.9%
Delafield town0.2%
Genesee town0.1%
Dousman village0.1%

Congressional district

Congressional districtShare of ZIP residents
Wisconsin's 5th congressional district (WI-05)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (WI-05)Scott Fitzgerald (R)202-225-5101100%
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 33)Chris Kapenga (R)100%
Assembly Member (Assembly District 99)Barbara Dittrich (R)82%
Assembly Member (Assembly District 97)Cindi Duchow (R)18%

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 33100%

State house districtShare of ZIP residents
Assembly District 9982%
Assembly District 9718%

Voting precincts

45 voting precincts overlap ZIP 53066. Map them, with each precinct's share of the ZIP's residents.

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ZIP 53066 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.