New Castle, NH ZIP code
The ZIP code for New Castle, New Hampshire is 03854. It is in Rockingham County.
- Population in these ZIPs
- 827
- Avg. median income
- $177,000population-weighted
- Typical home value
- $2,503,500population-weighted
- Metro area
- Boston-Cambridge-Newton, MA-NH
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New Castle, NH ZIP code list
| ZIP code | Population | Median income | Typical home value |
|---|---|---|---|
| 03854 | 827 | $176,953 | $2,503,500 |
Population and median household income: ACS 2020–2024 5-year estimates. Typical home value: Zillow Home Value Index (September 2026) where available, otherwise the ACS median owner-reported value. "PO Box" marks ZIP codes with no delivery area of their own. Methodology
Cities near New Castle
- Portsmouth 3 mi
- Rye 4 mi
- Rye Beach 6 mi
- Greenland 7 mi
- North Hampton 8 mi
- Stratham 10 mi
- Durham 11 mi
- Newmarket 12 mi
- Dover 12 mi
- Hampton 12 mi
- Rollinsford 13 mi
- Hampton Falls 13 mi
Frequently asked questions
What is the ZIP code for New Castle, NH?
The ZIP code for New Castle, NH is 03854.
What county is New Castle, New Hampshire in?
New Castle ZIP codes are in Rockingham County.