Boundary Atlas

ZIP code 80303: Boulder, CO

ZIP code 80303 is in Boulder (84% of residents) and Paragon Estates (3.9%), in Boulder County, Colorado. 12% of its residents live outside city limits. It is in Colorado's 2nd congressional district. Its state senate districts are State Senate District 18 (98%) and State Senate District 15 (1.6%); its state house districts are State House District 10 (84%), State House District 12 (14%) and State House District 49 (1.6%).

25,328residents (2020 Census)
21.9 sq miland area
4cities and towns
1congressional district
20voting precincts

See it on the mapAll of Colorado

City and county

City or townShare of ZIP residents
Boulder84%
Paragon Estates3.9%
Eldorado Springs1.0%
Louisville0.1%

CountyShare of ZIP residents
Boulder County100%

Town or county subdivisionShare of ZIP residents
Boulder CCD95%
Lafayette-Louisville CCD5.3%

Congressional district

Congressional districtShare of ZIP residents
Colorado's 2nd congressional district (CO-02)100%

Elected officials

OfficeMemberContactShare of residents
MayorAaron Brockett84%
U.S. Representative (CO-02)Joe Neguse (D)202-225-2161100%
U.S. SenatorJohn W. Hickenlooper (D)202-224-5941 · contact formstatewide
U.S. SenatorMichael F. Bennet (D)202-224-5852 · contact formstatewide
State Senator (State Senate District 18)Judy Amabile (Democratic)98%
State Senator (State Senate District 15)Janice Marchman (Democratic)1.6%
State Representative (State House District 10)Junie Joseph (Democratic)84%
State Representative (State House District 12)Kyle Brown (Democratic)14%
State Representative (State House District 49)Lesley Smith (Democratic)1.6%

From Wikidata (community-maintained); confirm on the city's website.

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); Mayors: Wikidata (CC0).

Local government

State legislative districts

State senate districtShare of ZIP residents
State Senate District 1898%
State Senate District 151.6%

State house districtShare of ZIP residents
State House District 1084%
State House District 1214%
State House District 491.6%

Voting precincts

20 voting precincts overlap ZIP 80303. Map them, with each precinct's share of the ZIP's residents.

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ZIP 80303 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.