Boundary Atlas

ZIP code 98240: Whatcom County, WA

ZIP code 98240 is in Custer (12% of residents), in Whatcom County, Washington. 88% of its residents live outside city limits. It is in Washington's 2nd congressional district. Its state senate district is Legislative (Senate) District 42; its state house district is Legislative (House) District 42.

3,118residents (2020 Census)
22.3 sq miland area
1cities and towns
1congressional district
6voting precincts

See it on the mapAll of Washington

City and county

City or townShare of ZIP residents
Custer12%

CountyShare of ZIP residents
Whatcom County100%

Town or county subdivisionShare of ZIP residents
Blaine CCD93%
Lynden CCD7.4%

Congressional district

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

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (WA-02)Rick Larsen (D)202-225-2605100%
U.S. SenatorMaria Cantwell (D)202-224-3441 · contact formstatewide
U.S. SenatorPatty Murray (D)202-224-2621 · contact formstatewide
State Senator (Legislative (Senate) District 42)Sharon Shewmake (Democratic)100%
State Representative (Legislative (House) District 42)Alicia Rule (Democratic)100%
State Representative (Legislative (House) District 42)Joe Timmons (Democratic)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
Legislative (Senate) District 42100%

State house districtShare of ZIP residents
Legislative (House) District 42100%

Voting precincts

6 voting precincts overlap ZIP 98240. Map them, with each precinct's share of the ZIP's residents.

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ZIP 98240 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.