| Place Name | Newcastle |
| Place Type | Census Designated Place |
| ZIP Code(s) | 95658 |
| County | Placer County |
| Area Code(s) | 279,916 |
| Timezone | Pacific Daylight Time (PDT) |
| Population (2022) | 1,247 |
| Population Growth Rate (2010-19) | 7.92% |
| Majority Ethnicity | White 82.5% |
| Metro/Micro Stats Area | Sacramento-Roseville-Folsom, CA |
| US Congressional District(s) | California 4th |
| State Assembly Districts | 5 |
| State Senate Districts | 1 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 82.5% |
| African American | 0% |
| Hispanic | 0.57% |
| Asian | 0.63% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 16.3% |