Boundary Atlas

ZIP code 46303: Cedar Lake, IN

ZIP code 46303 is in Cedar Lake (82% of residents) and St. John (1.6%), in Lake County, Indiana. 17% of its residents live outside city limits. It is in Indiana's 1st congressional district. Its state senate districts are State Senate District 6 (98%) and State Senate District 1 (1.6%); its state house districts are State House District 11 (86%), State House District 15 (8.9%) and State House District 19 (4.6%).

17,028residents (2020 Census)
28.8 sq miland area
2cities and towns
1congressional district
15voting precincts

See it on the mapAll of Indiana

City and county

City or townShare of ZIP residents
Cedar Lake82%
St. John1.6%

CountyShare of ZIP residents
Lake County100%

Town or county subdivisionShare of ZIP residents
Hanover township65%
Center township30%
West Creek township5.4%

Congressional district

Congressional districtShare of ZIP residents
Indiana's 1st congressional district (IN-01)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (IN-01)Frank J. Mrvan (D)202-225-2461100%
U.S. SenatorJim Banks (R)202-224-4814statewide
U.S. SenatorTodd Young (R)202-224-5623 · contact formstatewide
State Senator (State Senate District 6)Rick Niemeyer (R)98%
State Senator (State Senate District 1)Dan Dernulc (R)1.6%
State Representative (State House District 11)Mike Aylesworth (R)86%
State Representative (State House District 15)Hal Slager (R)8.9%
State Representative (State House District 19)Julie Olthoff (R)4.6%

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 698%
State Senate District 11.6%

State house districtShare of ZIP residents
State House District 1186%
State House District 158.9%
State House District 194.6%

Voting precincts

15 voting precincts overlap ZIP 46303. Map them, with each precinct's share of the ZIP's residents.

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ZIP 46303 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.