Newcastle city, Washington
Official LSAD Designation: Newcastle city • Census GEOID: 5348645
• King County
Newcastle city is an incorporated city in King County, Washington. According to official records from the Census (2025), Newcastle city had an estimated population of 13,128 residents. Official Census Bureau geographic records classify this community under LSAD designation Newcastle city (GEOID 5348645).
Local Government Administration U.S. Census Bureau GMAF
City Of Newcastle
Municipal
Official Title:
Mayor
Address:
12835 NEWCASTLE WAY, SUITE 200, NEWCASTLE WA 98056-1316
County Of King
County
Official Title:
Demographer
Address:
401 5TH AVE, STE 800, SEATTLE WA 98104-2391
Civic & Statistical Snapshot
| Category | Estimate | Survey Period / Source |
|---|---|---|
| Total Population | 13,128 | 2025 |
| Median Household Income | $160,278 | 2020-2024 |
| Median Home Value | $1,205,600 | 2020-2024 |
| Land Area | 4.44 sq mi | Gazetteer (2026) |
| Civic & Public Services | Hospitals, Libraries, Colleges | CMS / IMLS / IPEDS |
| Schools & Districts | NCES Directory Listings | Provided by k12guides.com |
| Nearby Airports | Landing Facilities | Provided by airport-data.com |
| Climate & Weather | NOAA 30-Year Normals | 1991–2020 |
Source: U.S. Census Bureau (PEP, ACS 5-Year).