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For Sale

350 Portsmouth Avenue

New Castle, NH 03854

$4,200,000

$1,297 per sq ft

Listed Aug 28 · 13 days on market

3

Beds

5

Baths

3,238

Sq ft

0.25

Acres

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

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.

Virtual tour

Schools

Maude H. Trefethen SchoolElementary
Rye Junior High SchoolMiddle
PortsmouthHigh

Key features

  • Cathedral Ceiling(s)
  • Ceiling Fan(s)
  • Dining Area
  • Wood Fireplace
  • 1 Fireplace
  • Kitchen Island
  • Primary BR w/ BA
  • Natural Light
  • Boat Mooring
  • Boat Slip
  • Hot Tub
  • Private Dock

See it with Kate and Jen.

We'll set up the showing, walk you through it, and tell you what we really think.

Details

TypeSingle family
StyleContemporary
Year built1977
Finished sq ft3,238
Lot0.25 acres
Garage2 spaces
BasementClimate Controlled, Daylight, Full, Partially Finished, Interior Stairs, Walk-Out Access
HeatingOil, Forced Air
CoolingCentral Air
WaterPublic
SewerPublic
RoofAsphalt Shingle
ConstructionWood Frame, Wood Siding
FlooringCarpet, Tile
Taxes$15,636 (2025)
ZoningRD RE
WaterfrontPiscataqua River
Days on market13
MLS #5107161
PrimeMLS

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