




$18,500,000
631 N Mashta Drive, Key Biscayne, FL 33149
Mashta Island
Beds
4 Beds
Baths
4.5 Baths
Living Area
2,255 Sq Ft
Lot
0.34 acres
Built
1958
Days Listed
2
Price Per Sq Ft
$8,204/sqft
Listed
Jul 30, 2026
Property Type
Single Family Residence
Property Overview
This 4-bedroom waterfront single family residence at 631 N Mashta Drive, Key Biscayne, FL 33149 in the Mashta Island community on 0.34 acres with 2,255 square feet of living area, built in 1958 is listed for $18,500,000. Notable MLS signals include Dock / Boat Access, Ocean Access, Pool.
MLS Public Remarks
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.
Key Biscayne Property Snapshot
Property Type
Residential
Sub Type
Single Family Residence
Stories
1
Total Baths
4.5
Building Area
3,720 sq ft
Lot Size
15,000 sq ft
Lot Profile
1/4 To Less Than 1/2 Acre LotLess Than 1 Acre Lot
Condition
ResaleUpdated/Remodeled
MLS #
B26058354
Waterfront, Boating & Outdoor
Waterfront
Yes
Waterfront
No Fixed Bridge, Ocean Access, Navigable Water, Seawall, Bayfront, Intracoastal
Dock
Yes
Boat Features
Private Dock, Electric Available
Private Pool
Yes
Pool Features
In Ground, Equipment Included
View
Pool, Water, Bay, Intracoastal
Patio / Porch
Patio - Covered, Patio - Open, Patio
Interior & Construction
Interior Features
Entrance Foyer, Walk-In Closet(s)
Primary Bedroom
Dual Sinks
Rooms
Dining Room, Kitchen, Living Room, Master Bedroom
Appliances
Electric Water Heater, Cooktop, Dryer, Dishwasher, ENERGY STAR Qualified Dishwasher, ENERGY STAR Qualified Freezer, ENERGY STAR Qualified Refrigerator, ENERGY STAR Qualified Washer, ENERGY STAR Qualified Dryer, Free-Standing Freezer, Microwave, Oven, Refrigerator, Water Heater, Washer, Electric Cooktop, Wine Refrigerator
Flooring
Concrete, Laminate, Tile
Construction
Brick, Concrete
Heating
Central, Electric
Cooling
Central Air
Furnished
Unfurnished
Impact Glass
Complete
Parking, HOA & Rules
Open Parking
6
Parking Features
Attached Carport, Circular Driveway, Driveway, Carport
Pets Allowed
Yes, No Restrictions
Restrictions
See Remarks
Taxes, Utilities & MLS
Annual Taxes
$112,485
Tax Year
2025
Parcel Number
2452050080070
Zoning
2001
County
Miami-Dade
MLS Area
2520
Sewer
Public Sewer
Water Source
Public
Utilities
Electricity Connected, Sewer Connected, Water Connected
Photos
8
Listing courtesy of Coldwell Banker
Listing Agent: Javier Gustavo Quiroz

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The data relating to real estate for sale on this website comes in part from the Internet Data Exchange (IDX) program of the BeachesMLS. Real estate listings held by brokerage firms other than Levin Investments, Inc are marked with the IDX logo and detailed information about them includes the name of the listing broker. Data provided is deemed reliable but is not guaranteed. All information is subject to change and should be independently verified.
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