| Place Name | New Castle |
| Place Type | Town |
| ZIP Code(s) | 03854 |
| County | Rockingham County |
| Area Code(s) | 603 |
| Timezone | Eastern Daylight Time (EDT) |
| Population (2021) | 817 |
| Majority Ethnicity | White 100% |
| Metro/Micro Stats Area | Boston-Cambridge-Newton, MA-NH |
| US Congressional District(s) | New Hampshire 1st |
| State House Districts | Rockingham 24 |
| State Senate Districts | 24 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 100% |
| African American | 0% |
| Hispanic | 0% |
| Asian | 0% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 0% |