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Adam Dow

| The Dow Group | #1 Real Estate Team in New Hampshire

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350 Portsmouth Ave , New Castle, NH 03854
$3,750,000
Est. Payment: $20,359.58/mo
3 Bed
4 Bath
3238 Sqft
0.25 Acres
Status: active | Days on site: 47
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House Description

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.

Highlights

Listed by Janet Sylvester , 603-433-3350 and Margaret Pesce , 603-433-3350 Great Island Realty LLC , 603-433-3350. PrimeMLS mls logo

Property Type

Residential

Lot/Acreage
0.25

Year Built

1977

County

Rockingham

School District

New Castle

Listing ID

5107161

Questions about this listing?

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Interior Features

Bedrooms and Bathrooms
  • ▪ Bedrooms:3
  • ▪ Bathrooms:4
  • ▪ Full Bathrooms:1
  • ▪ 3/4 Bathrooms:2
  • ▪ 1/2 Bathrooms:1
Appliances:Electric Cooktop, Dishwasher, Double Oven, Wall Oven, Refrigerator
Air Cond:Central AC
Fireplaces:
Floor:Carpet,Tile
Above Ground Sq Ft:2375
Basement:Yes,Climate Controlled,Daylight,Full,Partially Finished,Interior Stairs,Walkout
Other:
  • ▪ Additional:Cathedral Ceiling, Ceiling Fan, Dining Area, Wood Fireplace, 1 Fireplace, Kitchen Island, Primary BR w/ BA, Natural Light

Exterior Features

Lot:Existing,Waterfront,Piscataqua River, Waterbody Type: River, Waterbody Access: Exclusively Owned, Waterfront: 100 ft
Zoning:RD RE
Roof:Asphalt Shingle
Others:
  • ▪ Additional:Boat Mooring, Boat Slip/Dock, Hot Tub, Private Dock, Sauna, Deep Water Access, Dock Access
Sewer:Public
Parking Features:Auto Open,Direct Entry,Driveway,Attached
Principal Interest
$20,360
Taxes
$1,303

Home Price

$3,750,000

Loan Details

30 yrs
7.198%

Down Payment

20%
$750,000
All calculations are estimates and provided by Blueroof360. Today’s Rates provided by Blueroof360. Information and interactive calculators are made available to you only as self-help tools for your independent use and are not intended to provide investment or tax advice. We cannot and do not guarantee their applicability or accuracy in regards to your individual circumstances. All examples are hypothetical and are for illustrative purposes. We encourage you to seek personalized advice from qualified professionals regarding all personal finance issues.
Monthly Price:
$20,359.58

Principal

Taxes

Principal Taxes HOA Total
Monthly $20,359.58 $1,303.00 $0.00 $21,662.58
Yearly $244,315.02 $15,636.00 $0.00 $259,951.02
Total $7,329,450.50 $469,080.00 $0.00 $7,798,530.50

Today's Rates

30 Year

7.2%

20 Year

6.62%

15 Year

6.52%

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Market insight data is pulled from the same city as the listing being viewed (New Castle, NH).

The schools listed are within a 2-mile radius of the property; however, attendance is not guaranteed. Please contact the local school district to confirm zoning and enrollment options.

Copyright 2026 PrimeMLS, Inc. All rights reserved. This information is deemed reliable, but not guaranteed. The data relating to real estate displayed on this display comes in part from the IDX Program of PrimeMLS. The information being provided is for consumers’ personal, non-commercial use and may not be used for any purpose other than to identify prospective properties consumers may be interested in purchasing. Data last updated October 31, 2026 5:01pm

Data last updated: 2026-10-31T21:01:58.800Z

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