New Castle NH Real Estate & Homes for Sale

There are 2 active MLS listings for homes in New Castle right now. Asking prices currently run from $2,400,000 to $3,750,000. This page reads the live feed, so the count changes as homes come on the market and go under contract.

Active listings for homes in New Castle currently average $3,075,000 with a median asking price of $3,750,000. Averages move with the mix of homes on the market at any moment, so treat them as a snapshot rather than a valuation.

The active listings in New Castle have been on the market for an average of 34 days so far. Well-priced homes move faster than that average, so if you are watching this market it pays to see new listings the day they appear.

Use the Get Alerts button at the top of this page — it saves exactly this search and emails you when a matching listing hits the MLS. Or contact our local team and tell us what you're looking for; we watch this market every day.

New Castle, NH uses ZIP code 03854. The town is in Rockingham County, New Hampshire.

New Castle's 2025 total property tax rate is $5.73 per $1,000 of assessed value (municipal, county, local and state education combined), per the New Hampshire Department of Revenue Administration. Village or water districts can add to it, and the bill depends on the assessed value, not the sale price.

New Castle is in Rockingham County at the mouth of the Piscataqua River, on Great Island and several smaller islands. It borders Kittery, Maine to the north, Rye to the southwest and Portsmouth to the west, and it is the easternmost town in New Hampshire. Two bridges and a causeway connect it to Portsmouth.

New Castle is known for Fort Constitution and Fort Stark state historic sites, Portsmouth Harbor Light, the 31-acre New Castle Common on the Atlantic and the Wentworth by the Sea hotel. The 1774 raid on Fort William and Mary, now Fort Constitution, was one of the first acts of the American Revolution.

Yes. New Castle is the only New Hampshire town located entirely on islands. It occupies a small archipelago of one main island, Great Island, and several smaller ones, surrounded by the Piscataqua River and the Atlantic Ocean. Of its 2.3 square miles, only about 0.81 square miles is land.

With well under a square mile of land, New Castle has a compact, historic housing stock. The town was long a quiet fishing village, which helped preserve its colonial architecture, and homes sit close to the harbor, Little Harbor or the ocean. Its small land area means relatively few homes come up for sale.