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9 Walnut Street, 
Cos Cob, CT 06807

$1,575,000

3

Beds

1

Bath

-

Sq Ft

0.52

Acres (Lot)

Land

Active

Listed by

Peter Janis

Bhhs New England Properties

Last updated:

February 10, 2026, 03:24 PM

MLS#

123887

Source:

CT GAR

About This Land

9 Walnut Street

.52 Acre Buildable Lot with Existing Cottage — North Mianus Nestled at the end of a private road in the desirable North Mianus neighborhood, this .52-acre property offers a unique combination of privacy, potential, and flexibility. The lot is fully entitled with plans to build a 4,200 sq. ft. custom home, making it ideal for builders, investors, or end-users looking to create their dream residence. In addition to the new-construction opportunity, the property includes an existing 1-bedroom, 1-bathroom cottage that is grandfathered in—perfect for rental income, a guest house, or an in-law suite while the main home is being built. This is a rare offering in one of Greenwich's most sought-after areas, within the North Mianus Elementary and Eastern Middle School districts,

Land Facts

Description/Design:

Land

Lot Size (Acres)

0.52

MLS #:

123887

Last Updated:

February 10, 2026, 03:24 PM

Added:

3 month(s) ago

Rooms & Interior

Bedrooms

Total Bedrooms:

3

Bathrooms

Total Bathrooms:

1

Full Bathrooms:

1

Interior

Living Area:

1,482 Sq. Ft.

Structure

Structure

Architectural Style:

Colonial

Building Area:

1,482 Sq. Ft.

Year Built:

1970

Finances & Disclosures

Finances

Price:

$1,575,000

Price per Sq. Ft:

$1,062 per Sq. Ft.

Source:CT GAR
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Contact an Agent

Yes, I would like more information. Please use and/or share my information with a Coldwell Banker ® affiliated agent to contact me about my real estate needs. By clicking Contact, I request to be contacted by phone or text message and consent to being contacted by automated means. I understand that my consent to receive calls or texts is not a condition of purchasing any property, goods, or services. Alternatively, I understand that I can access real estate services by email or I can contact the agent myself.

If a Coldwell Banker affiliated agent is not available in the area where I need assistance, I agree to be contacted by a real estate agent affiliated with another brand owned or licensed by Anywhere Real Estate (BHGRE®, CENTURY 21®, Corcoran®, ERA®, or Sotheby's International Realty®). I acknowledge that I have read and agree to the terms of use and privacy notice.