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$18,500,0009 days on marketActive

631 N Mashta Drive, Key Biscayne, FL 33149

Key Biscayne, FL 33149
4
Beds
4.5
Baths
2,255
Sq Ft
$8,204
$/Sq Ft
1958
Year Built
0.34 acres
Lot Size

Listing Snapshot

List Price$18,500,000
Price / Sq Ft$8,204
Beds4
Baths4.5
Living Area2,255 sqft
Lot Size0.34 acres
Year Built1958
Property Tax$112,485/yr
MLS #1178589130
StatusActive
Days on Market9

About This Home

BRING ALL OFFERS! Exceptional waterfront opportunity in prestigious Key Biscayne. Set on a 15,000 sq. ft. lot with 100 feet of water frontage, this residence offers open-water views, direct Biscayne Bay access, and no fixed bridges to the ocean. Currently undergoing a complete renovation, it will feature modern finishes, impact windows and doors, new systems, spacious living areas, a chef's kitchen, and luxurious bathrooms. Enjoy a private dock, deep-water access, pool, breathtaking sunsets, and an unmatched boating lifestyle in one of South Florida's most desirable communities One of the most compelling waterfront opportunities currently available in all of Key Biscayne. Perfectly positioned on the exclusive and highly coveted Mashta Island, this exceptional property offers approximately 100 feet of prime waterfront, deep-water dockage, direct Biscayne Bay access, and no fixed bridges to the Atlantic Ocean, creating an unparalleled opportunity for boating enthusiasts and yacht owners. Mashta Island has long been recognized as one of South Florida's most prestigious residential enclaves, offering exceptional privacy, quiet tree-lined streets, oversized waterfront estates, and immediate access to the open waters of Biscayne Bay while remaining only minutes from Brickell, Downtown Miami, Coconut Grove, Coral Gables, Miami Beach, and Miami International Airport. Very few neighborhoods offer this combination of island living, security, boating lifestyle, and proximity to the city's financial and cultural centers. The residence is currently on renovation designed to transform the property into a contemporary waterfront estate while preserving the exceptional value of its location and oversized waterfront parcel. This is substantially more than a cosmetic renovation. The project includes major improvements throughout the residence, including redesigned living spaces, upgraded electrical and plumbing systems, new HVAC equipment, impact-resistant windows and doors, premium flooring, modern architectural lighting, designer finishes, and a completely reimagined interior intended to meet today's luxury lifestyle expectations. Upon completion, the home is anticipated to offer spacious entertaining areas, beautifully appointed bedroom suites, bathrooms, an impressive chef's kitchen featuring custom cabinetry, premium appliances, elegant countertops, and thoughtfully designed indoor-outdoor living spaces that maximize the spectacular waterfront setting. The property's exceptional orientation provides beautiful water views and unforgettable sunsets while creating an ideal environment for entertaining, family gatherings, and year-round outdoor living. The expansive backyard offers generous space surrounding the swimming pool together with multiple areas for outdoor dining, lounging, and enjoying the waterfront lifestyle that has made Key Biscayne one of the most desirable residential communities in South Florida. For boating enthusiasts, few properties can offer the combination of oversized waterfront, private dockage, deep-water access, and unrestricted navigation to Biscayne Bay and the Atlantic Ocean without fixed bridges. Whether accommodating a large sport yacht, cruising yacht, center console, or multiple vessels, the waterfront configuration provides flexibility rarely available in today's market. Key Biscayne continues to be recognized as one of South Florida's most exclusive island communities, celebrated for its pristine beaches, excellent schools, private clubs, marinas, tennis facilities, parks, bicycle paths, restaurants, and relaxed coastal lifestyle. Residents enjoy the unique advantage of living within a peaceful island environment while remaining only a short drive from Miami's world-class shopping, fine dining, cultural institutions, private airports, international business centers, and professional sports venues. The supply of premium waterfront homes on Mashta Island remains extremely limited due to the neighborhood's established character and finite number of waterfront parcels. As a result, opportunities to acquire large waterfront lots with substantial dockage and direct ocean access continue to be highly sought after by both domestic and international buyers. The combination of location, waterfront dimensions, boating accessibility, oversized lot, and comprehensive renovation creates a property with exceptional long-term appeal. Showings are strictly by appointment with the Listing Agent.. All measurements, dimensions, lot size, square footage, waterfront frontage, dock dimensions, room sizes, zoning, taxes, permits, specifications, plans, renderings, and property information are believed to be accurate but are not guaranteed and should be independently verified by Buyer. Renderings, conceptual plans, floor plans, specifications, and construction updates are available upon request when applicable. This offering represents an extraordinary opportunity to secure one of Key Biscayne's waterfront residences . Whether as a primary residence, seasonal retreat, or long-term investment, this property combines one of South Florida's most desirable locations with an outstanding boating lifestyle and exceptional future value. Bring All Offers.

General Features

Property Type
Residential
Sub-type
SingleFamilyResidence
Stories
1
Direction Faces
East
Parking Spaces
8
Parking
AttachedCarport,CircularDriveway,Carport,Driveway
Zoning
2001
Utilities
ElectricityConnected,SewerConnected,WaterConnected
Subdivision
MASHTA ISLAND

Interior Features

Appliances
Cooktop,Dryer,Dishwasher,EnergyStarQualifiedDishwasher,EnergyStarQualifiedDryer,EnergyStarQualifiedFreezer,EnergyStarQualifiedRefrigerator,EnergyStarQualifiedWasher,ElectricCooktop,ElectricWaterHeater,FreeStandingFreezer,Microwave,Oven,Refrigerator,WaterHeater,WineRefrigerator,Washer
Flooring
Concrete,Laminate,Tile
Heating
Central,Electric
Cooling
CentralAir
Interior Features
DualSinks,EntranceFoyer,LivingDiningRoom,WalkInClosets
Laundry
Inside,LaundryRoom,LaundryTub,Sink
Window Features
StormWindows
Furnished
Unfurnished

Exterior Features

Construction
Brick,Concrete
Exterior Features
Garden,OutdoorLivingArea
Roof
Shingle
Lot Features
QuarterToHalfAcreLot,SprinklersAutomatic,SprinklerSystem
Patio / Porch
Covered,Patio,Rooftop
Pool
Yes
Pool Features
InGround,PoolEquipment
View
Bay,Intercoastal,Pool,Water
Waterfront
Yes
Waterfront Features
Bayfront,IntracoastalAccess,NavigableWater,NoFixedBridges,OceanAccess,Seawall

Community Features

MLS Area
2520

Schools

ElementaryKey Biscayne K-8
MiddlePonce De Leon
HighCoral Gables

Map

Virtual Tour

View Virtual Tour
Listed by Javier Quiroz · Coldwell Banker
MLS# 1178589130 · BEACH
Information deemed reliable but not guaranteed. © 2026 BEACH.

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Estimate Your Payment

$

20% down · Loan: $14,800,000

%
Est. Monthly$110,336
Principal & Interest$100,962
Property Tax$9,374

Estimate only. Does not include insurance or PMI. Rate is illustrative — contact us for current rates.

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