Newcastle city, Washington
Official LSAD Designation: Newcastle city • Census GEOID: 5348645
• King County
Demographics & Population Profile
Population and demographics for Newcastle city.
| Demographic Variable | Estimate / Count | Margin of Error | Period | Source |
|---|---|---|---|---|
| Total Population (2025 PEP Estimate) | 13,128 | — | 2025 | Census |
| Median Age | 37.5 yrs | ±2 | 2020-2024 | Census ACS 5-Year 2024 |
| Total Households | 5,416 | ±272 | 2020-2024 | Census ACS 5-Year 2024 |
Source: U.S. Census Bureau (PEP, ACS 5-Year).