Boundary Atlas

ZIP code 98528: Belfair, WA

ZIP code 98528 is in Belfair (39% of residents), in Mason County (100%) and Kitsap County (0.2%), Washington. 61% of its residents live outside city limits. It is in Washington's 6th congressional district. Its state senate district is Legislative (Senate) District 35; its state house district is Legislative (House) District 35.

11,052residents (2020 Census)
72.3 sq miland area
1cities and towns
1congressional district
13voting precincts

See it on the mapAll of Washington

City and county

City or townShare of ZIP residents
Belfair39%

CountyShare of ZIP residents
Mason County100%
Kitsap County0.2%

Town or county subdivisionShare of ZIP residents
Belfair-Tahuya CCD67%
Union-Grapeview CCD33%
Bremerton CCD0.2%

Congressional district

Congressional districtShare of ZIP residents
Washington's 6th congressional district (WA-06)100%

State legislative districts

State senate districtShare of ZIP residents
Legislative (Senate) District 35100%

State house districtShare of ZIP residents
Legislative (House) District 35100%

Voting precincts

13 voting precincts overlap ZIP 98528. 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:98528")

ZIP 98528 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.