About this home
Welcome to 350 Portsmouth Avenue, an exceptional waterfront residence offering a front row seat to one of the most captivating maritime settings on the New Hampshire Seacoast. With expansive water views of the Piscataqua River and Back Channel, this remarkable property captures everything that makes New Castle waterfront living so special. From magnificent ships and iconic Portsmouth tugboats to sailboats, fishing vessels and pleasure craft, the ever changing boat traffic provides a spectacular backdrop from morning until night. A private deep water dock makes this a dream for boating enthusiasts, offering direct access to Portsmouth Harbor, the Piscataqua River and the open Atlantic. Adding to the property's unique appeal is deeded access to the Back Channel, creating a wonderful launching point for kayaks and paddleboards. Designed to embrace this extraordinary setting, the home features multiple waterfront decks for entertaining, outdoor dining or simply watching the river come alive. A walk-out lower level extends the living space outdoors, while the hot tub and sauna create a private waterfront retreat to enjoy throughout the seasons. Enjoy all the amenities that make New Castle one of the Seacoast's most coveted communities, the nearby yacht clubs, Wentworth Marina, Wentworth by the Sea Country Club, Great Island Common, beaches and the historic charm of island living, all just minutes from downtown Portsmouth. And with New Castle's exceptionally low property taxes, this is a rare opportunity to combine an extraordinary waterfront lifestyle with one of New Hampshire's most desirable communities. Deep water boating out your front door. Kayaking and paddleboarding from your deeded Back Channel access. Incredible water views, spectacular boat traffic, waterfront decks, hot tub and sauna, all in the heart of New Castle. 350 Portsmouth Avenue isn't simply a waterfront home, it's a lifestyle defined by the water.
Listing last checked: Listing updated:
Listed by Janet Sylvester, Margaret Pesce · Great Island Realty LLC · MLS #5107161
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Details at a glance
Interior5 property facts
- Rooms
- 7
- Heating
- Oil, Forced Air
- Cooling
- Central Air
- Flooring
- Carpet, Tile
- Basement
- Yes · Climate Controlled, Daylight, Full, Partially Finished, Interior Stairs, Walkout
Building5 property facts
- Style
- Single Family Residence
- Year built
- 1977
- Garage
- 2
- Parking
- 2
- Roof
- Shingle
Land & utilities6 property facts
- Lot size
- 0.25 acres
- Water
- Public
- Sewer
- Public Sewer
- Waterfront
- Y
- Pool
- Not reported
- Zoning
- RD RE
Financial2 property facts
- Annual taxes
- $15,636
- Assessment year
- 2025
Location
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Estimated monthly cost
Explore costs at the $3,750,000 asking price. Adjust the assumptions to your situation.
Known monthly costs$20,265 / monthAdjust
- Principal & interest
- $18,962
- Property tax
- $1,303
- Insurance
- Not entered
- HOA
- Not entered
Listing annual taxes: $15,636. Initial monthly tax is one twelfth of that amount. HOA amount was not supplied.
Partial estimate: add insurance, monthly HOA to include those costs. Blank amounts are unknown.
The initial 6.5% rate is illustrative, not a current rate or lender quote. Excludes utilities, maintenance, closing costs and mortgage insurance, which may apply with a down payment below 20%. Taxes and insurance can change.
More property insights
Photo-based condition insights
Overall presentation: above average
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About 350 Portsmouth Avenue
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Request a tour of 350 Portsmouth Avenue and a Bean Group agent will help coordinate an available time with the listing side.
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Yes. We can discuss condition, comparable sales, offer strategy and the questions worth asking before you decide whether to proceed.
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