Boundary Atlas

ZIP code 80403: Fairmount, CO

ZIP code 80403 is in Fairmount (32% of residents), Golden (25%), Arvada (13%) and Coal Creek (12%), in Jefferson County (94%), Boulder County (3.7%) and Gilpin County (2.4%), Colorado. 18% of its residents live outside city limits. It is in Colorado's 7th congressional district (85%) and Colorado's 2nd congressional district (15%). Its state senate districts are State Senate District 20 (55%), State Senate District 22 (25%), State Senate District 19 (13%), State Senate District 15 (3.7%) and State Senate District 8 (2.4%); its state house districts are State House District 27 (48%), State House District 24 (46%) and State House District 49 (6.1%).

21,335residents (2020 Census)
142.0 sq miland area
4cities and towns
2congressional districts
20voting precincts

See it on the mapAll of Colorado

City and county

City or townShare of ZIP residents
Fairmount32%
Golden25%
Arvada13%
Coal Creek12%

CountyShare of ZIP residents
Jefferson County94%
Boulder County3.7%
Gilpin County2.4%

Town or county subdivisionShare of ZIP residents
Golden CCD80%
Northeast Jefferson CCD14%
Bald Mountain CCD3.7%
Central City CCD2.4%

Congressional districts

Congressional districtShare of ZIP residents
Colorado's 7th congressional district (CO-07)85%
Colorado's 2nd congressional district (CO-02)15%

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
U.S. Representative (CO-07)Brittany Pettersen (D)202-225-264585%
U.S. Representative (CO-02)Joe Neguse (D)202-225-216115%
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 20)Lisa Cutter (Democratic)55%
State Senator (State Senate District 22)Jessie Danielson (Democratic)25%
State Senator (State Senate District 19)Lindsey Daugherty (Democratic)13%
State Senator (State Senate District 15)Janice Marchman (Democratic)3.7%
State Senator (State Senate District 8)Dylan Roberts (Democratic)2.4%
State Representative (State House District 27)Brianna Titone (Democratic)48%
State Representative (State House District 24)Lisa Feret (Democratic)46%
State Representative (State House District 49)Lesley Smith (Democratic)6.1%

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 2055%
State Senate District 2225%
State Senate District 1913%
State Senate District 153.7%
State Senate District 82.4%

State house districtShare of ZIP residents
State House District 2748%
State House District 2446%
State House District 496.1%

Voting precincts

20 voting precincts overlap ZIP 80403. Map them, with each precinct's share of the ZIP's residents.

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ZIP 80403 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.