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Listed by Janet Sylvester with Great Island Realty LLC 603-433-3350
3 Beds
5 Baths
3,238 sqft

$4,200,000

350 Portsmouth Avenue, New Castle NH, 03854

Price per sqft$1,297.10
Built in1977
Property size3,238 sqft
Property typeResidential

Overview

Active

Listed Aug 28, 2026

Updated 9 days ago

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.

$27,943/mo

Est. mortgage payment based on a $4,200,000 home price.

All estimates are provided by Luxury Presence for informational purposes only. Actual amounts may vary.

Additional information

MLS® ID
5107161

Interior Features

Bedrooms
3
Bathrooms
5
Fireplace
Yes
Cooling
Yes
Heating
Yes
Basement
Yes

Exterior Features

Lot Size
0.25 Acres

Other Property Details

Taxes
$15,636
Tax Frequency
Annually
Garage
Yes
Waterfront
Yes
MLS provider logo

Listed by Janet Sylvester with Great Island Realty LLC 603-433-3350

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