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$2,400,000

  • For Sale
  • Active
  • Single Family
  • 6 Beds
  • 2 Full Baths
  • 2 Partial Baths
  • 3,730 Sq. Ft.
  • 0.25 Acres
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Experience exceptional living in this rare 6-bedroom, 4-bath home set on a beautifully wooded and private lot in desirable New Castle, NH. Designed for both everyday comfort and impressive entertaining. This home features an open-concept kitchen and living area with soaring cathedral ceilings that create a sense of light and spaciousness. The chef's kitchen is equipped with top-of-the-line appliances and an spacial flow into the main living space. A stunning stone fireplace anchors the room, offering warmth and architectural impact. With its unusually generous square footage for New Castle, this home provides remarkable flexibility-ideal for living, hosting guests, and dedicated work and creative spaces. Enjoy peaceful, wooded surroundings just moments from the coast. Combining space, privacy, and New Castle's coveted low tax rate, this property offers an outstanding opportunity in one of New Hampshire's most sought-after communities.

Full Property Details for 18 Mainmast Cir

General

  • Price: $2,400,000
  • Status: Active
  • Type: Single Family
  • Source: PrimeMLS
  • MLS ID: 5070418
  • Updated: 12/18/2025
  • Added to Site: 56 day(s) ago

Interior

  • Number of Rooms: 9
  • Interior Features: Wood Fireplace, Wood Stove Hookup
  • Fireplace: Yes
  • Appliances: Gas Cooktop, Dishwasher, Double Oven, Refrigerator
  • Flooring: Hardwood, Tile

Rooms

Bathrooms

  • Total Bathrooms: 4
  • Full Bathrooms: 2
  • 3/4 Bathrooms: 1
  • Half Bathrooms: 1

Bedrooms

  • Total Bedrooms: 6

Exterior

  • Color: natural

Location

  • County: Rockingham
  • Driving Directions: Turn onto Walton Road off 1B in New Castle, continue until road curves to the right, house is second on right on Mainmast Circle,

School Information

  • School District: Portsmouth
  • Elementary School: Maude H. Trefethen School
  • Middle School: Rye Junior High School
  • High School: Portsmouth High School

Heating & Cooling

  • Cooling Type: None
  • Heating Type: Hot Air

Utilities

  • Sewer: Pump Up

Structural Information

  • Construction Status: Existing
  • Basement Entrance: Interior
  • Basement Desc.: Basement Stairs
  • Roof: Asphalt Shingles
  • Stories/Levels: 3
  • Square Feet: 3,730
  • Finished Total: 3,730 Sq. Ft.
  • Finished Above Grnd: 3,243 Sq. Ft.
  • Finished Below Grnd: 487 Sq. Ft.
  • Year Built: 1974

Lot Features

  • Lot Size (Acres): 0.25
  • Lot Size (Sq. Ft.): 10,890
  • Frontage: Yes Road Frontage
  • Frontage Feet: 111
  • Driveway/Sidewalk: Gravel
  • Zoning: residential

Financial Considerations

  • Price Per Sq. Ft.: $643.43

Disclosures and Reports

  • Surveyed: Yes
  • Lot Number: 7

Listed by The Aland Realty Group, Susan Spaulding

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Listed by The Aland Realty Group, Susan Spaulding

Listing agent

— 18 Mainmast Cir —

  • Susan Spaulding

    The Aland Realty Group

Get Pre-Approved Today

Be ready to buy your new home!

with our affiliated lender
NMLS#: 1598647

Get Pre-Approved

Be ready to buy your new home!

with our affiliated lender
NMLS#: 1598647

Get Pre-Approved

Schools serving 18 Mainmast Cir

School District:New Castle School District
NameGradesDistance
Maude H. Trefethen School
142 Cranfield Street, New Castle, NH 03854
K-50.2 mi
Disclaimer: School attendance boundaries provided by Pitney Bowes and are for reference only. Contact the school directly to verify enrollment eligibility.

Price & Sales History for 18 Mainmast Cir Get Price Alerts and Save Property

Date
Details
Price
Change
Source
11/21/2025
Listed
$2,400,000
389.8%
MLS
5/12/2005
Sold
$490,000
—
Public Record
Get Price Alerts and Save Property
Disclaimer: Historical sales information is derived from public records provided by the county offices. Information is not guaranteed and should be independently verified.

Tax History for 18 Mainmast Cir

Year
Property Taxes
Change
Tax Assessment
Change
2024
$5,809
7%
$1,077,700
-1%
2023
$5,432
11%
$1,090,700
—
2022
$4,887
-6%
$1,086,000
—
2021
$5,191
3%
$1,086,000
35%
2020
$5,059
2%
$803,000
—
2019
$4,971
3%
$803,000
—
2018
$4,818
3%
$803,000
—
2016
$4,697
10%
$802,900
21%
2015
$4,253
-3%
$664,500
—
2014
$4,386
3%
$664,500
—
2013
$4,246
—
$664,500
—
View All
Disclaimer: Historical tax information is derived from public records provided by the county offices. Information is not guaranteed and should be independently verified.

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*These costs are estimates, and the interest rates assume exceptional credit standing.

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NMLS#: 1598647

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Listed by The Aland Realty Group, Susan Spaulding

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18 Mainmast Circle, New Castle, NH 03854 (MLS# 5070418) is a Single Family property with 6 bedrooms, 2 full bathrooms and 2 partial bathrooms. 18 Mainmast Circle is currently listed for $2,400,000 and was received on November 21, 2025. Want to learn more about 18 Mainmast Circle? Do you have questions about finding other Single Family real estate for sale in New Castle? You can browse all New Castle real estate or contact a Coldwell Banker agent to request more information.

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