640 S Mashta Drive, Key Biscayne, FL 33149

Key Biscayne, FL 33149
$16,800,000
Beds
4
Baths
4
Living Area
3,620 SF
Year Built
1968
$/SF
$4641
Type
SingleFamilyResidence
DOM
59
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About this property

4 bed · 4 bath · 3,620 sqft · Built 1968

Welcome to your own slice of paradise! Enjoy breathtaking sunsets from your private dock on this waterfront property boasting 100 feet of direct Biscayne Bay frontage. Ideally located on Mashta Island. Set on a 15,000 SF lot, the home features 5 beds, 5 baths, including 2 bayfront primary suites with stunning views, impact windows and doors throughout. The open-concept layout flows seamlessly from the living and dining areas to the modern kitchen and out to the pool and entertainment patio, with floor-to-ceiling glass doors that open to blend indoor and outdoor living. Tranquil guest suite upstairs offering privacy and views. It also features an oversized 2-car garage, covered parking, and a spacious driveway for guests. Perfect to move in, renovate, or build your dream waterfront estate

Property facts
Property type
SingleFamilyResidence
Condition
Resale
Year built
1968
Roof
Barrel
Subdivision
MASHTA ISLAND
Waterfront
Yes
Waterfront features
OceanFront
Private pool
Yes
Public records
Parcel number
2452050080320
Annual tax
$155,651
County just value
$9,910,420
The neighborhood

Key Biscayne is a barrier-island enclave — restricted access, oceanfront SFH, and an inventory measured in tens, not hundreds. Premiums reflect the geography.

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Listing data sourced from BeachesMLS / Trestle. All information herein is deemed reliable but is not guaranteed and should be independently verified. Information last updated 5/31/2026. Represented by Eleven Realty Partners, LLC d/b/a XI Realty · Equal Housing Opportunity.

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