Boundary Atlas

ZIP code 98611: Castle Rock, WA

ZIP code 98611 is in Castle Rock (24% of residents), in Cowlitz County, Washington. 76% of its residents live outside city limits. It is in Washington's 3rd congressional district. Its state senate districts are Legislative (Senate) District 19 (64%) and Legislative (Senate) District 20 (36%); its state house districts are Legislative (House) District 19 (64%) and Legislative (House) District 20 (36%).

10,165residents (2020 Census)
136.1 sq miland area
1cities and towns
1congressional district
14voting precincts

See it on the mapAll of Washington

City and county

City or townShare of ZIP residents
Castle Rock24%

CountyShare of ZIP residents
Cowlitz County100%

Town or county subdivisionShare of ZIP residents
Castle Rock CCD97%
Rose Valley CCD2.5%
Northeast Cowlitz CCD0.2%

Congressional district

Congressional districtShare of ZIP residents
Washington's 3rd congressional district (WA-03)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (WA-03)Marie Gluesenkamp Perez (D)202-225-3536100%
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 19)Jeff Wilson (R)64%
State Senator (Legislative (Senate) District 20)John Braun (R)36%
State Representative (Legislative (House) District 19)Jim Walsh (R)64%
State Representative (Legislative (House) District 19)Joel McEntire (R)64%
State Representative (Legislative (House) District 20)Ed Orcutt (R)36%
State Representative (Legislative (House) District 20)Peter Abbarno (R)36%

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 1964%
Legislative (Senate) District 2036%

State house districtShare of ZIP residents
Legislative (House) District 1964%
Legislative (House) District 2036%

Voting precincts

14 voting precincts overlap ZIP 98611. Map them, with each precinct's share of the ZIP's residents.

Get this in your AI agent

Your agent can get these cities, counties, districts and precincts with their shares, and their GeoJSON boundaries, from Boundary Atlas. Add https://atlas-production-d344.up.railway.app/mcp to Claude, ChatGPT, Cursor or Codex (free, no key; how), then:

related_geographies(id="us:zcta:98611")

ZIP 98611 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.