Newcastle, Washington
Newcastle is a city in King County, Washington, with 13,017 residents in 2020. It is in Washington's 9th congressional district. Its state senate district is Legislative (Senate) District 41; its state house district is Legislative (House) District 41.
County
| County | Share of residents |
|---|---|
| King County | 100% |
Congressional district
| Congressional district | Share of residents |
|---|---|
| Washington's 9th congressional district (WA-09) | 100% |
Elected officials
| Office | Member | Contact | Share of residents |
|---|---|---|---|
| U.S. Representative (WA-09) | Adam Smith (D) | 202-225-8901 | 100% |
| U.S. Senator | Maria Cantwell (D) | 202-224-3441 · contact form | statewide |
| U.S. Senator | Patty Murray (D) | 202-224-2621 · contact form | statewide |
| State Senator (Legislative (Senate) District 41) | Lisa Wellman (Democratic) | 100% | |
| State Representative (Legislative (House) District 41) | Janice Zahn (Democratic) | 100% | |
| State Representative (Legislative (House) District 41) | My-Linh Thai (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
- Newcastle website: https://newcastlewa.gov
- Newcastle laws: search for the Newcastle, Washington code of ordinances
- King County website: https://kingcounty.gov
- King County laws: search for the King County, Washington code of ordinances
State legislative districts
| State senate district | Share of residents |
|---|---|
| Legislative (Senate) District 41 | 100% |
| State house district | Share of residents |
|---|---|
| Legislative (House) District 41 | 100% |
ZIP codes
Percentages mark ZIPs only partly in Newcastle: the share of that ZIP's residents living in it.
Get this in your AI agent
Your agent can get Newcastle's counties and districts with shares, its ZIP codes (level='zcta'), and its boundary as GeoJSON (get_boundaries). Add https://boundarymcp.com/mcp to Claude, ChatGPT, Cursor or Codex (free, no key; how), then:
related_geographies(id="us:place:5348645")
Newcastle here is the Census Bureau's place boundary as of January 1, 2025. Shares are of 2020 Census population. Districts are the maps in force for the November 3, 2026 election.