631 N Mashta Drive, Key Biscayne, FL 33149 (MLS# B26058354)

631 N Mashta Drive, Key Biscayne, FL 33149

New Listing
$18,500,000
Property Type: Residential Bedrooms: 4 Baths: 5 Square Footage: 3,720 Status: Active
Current Price: $18,500,000 List Date: 7/30/2026 Last Modified: 7/30/2026

Overview

Description

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

Supplements: 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 u ...

Listing Details MLS# B26058354

General Property Information

Property Sub Type
Single Family Residence
Bedrooms Total
4
Bathrooms Total
5
Bathrooms Full
4
Bathrooms Half
Yes
Building Area Main
3720
Building Area Source
Public Records
Living Area Main
2255
Living Area Source
Public Records
Adjusted Area Main
2779
Accessibility Features YN
No
Year Built
1958
Carport YN
Yes
Attached Carport YN
Yes
Carport Spaces
2
Covered Spaces
2
Parking Total
8
Gated Community YN
No
Lot Size Area
15000
Lot Size Acres
0.34
Frontage Length
100
Senior Community YN
No
Waterfront YN
Yes
Water Frontage Feet
100
Outdoor Living Spaces YN
Yes
Stories Total
Yes
Stories
Yes
Direction Faces
East
Fireplace YN
No
Pool Private YN
Yes
Green Verification YN
Yes
Furnished
Unfurnished

Property Features

Dining Area: Dining/Living Room Exterior Features: Garden; Private Rooftop Terrace Flooring: Concrete; Laminate; Tile Parking Features: Circular Driveway; Driveway; Attached Carport; Carport Property Condition: Resale; Updated/Remodeled Special Listing Conditions: Standard Appliances: Dishwasher; Dryer; Electric Cooktop; ENERGY STAR Qualified Dishwasher; ENERGY STAR Qualified Dryer; ENERGY STAR Qualified Freezer; ENERGY STAR Qualified Refrigerator; ENERGY STAR Qualified Washer; Free-Standing Freezer; Microwave; Oven; Refrigerator; Washer; Water Heater; Wine Refrigerator; Cooktop Water Heater Details: Electric Water Heater Boat and Dock Features: Electric Available; Private Dock Construction Materials: Brick; Concrete Cooling: Central Air Green Energy Efficient: Appliances; HVAC Heating: Central; Electric Interior Features: Entrance Foyer; Walk-In Closet(s) Laundry Features: Inside; Laundry Room; Sink Listing Terms: Cash; Conventional Membership: No Membership Available Pets Allowed YN: Yes Pets Allowed: No Restrictions Pool Features: Equipment Included; In Ground Possession: Close Of Escrow; Negotiable Restrictions: See Remarks Roof: Shingle Sewer: Public Sewer Sprinkler Description: Auto Sprinkler; Zoned Sprinkler Structure Type: House Tax Information: City/County Utilities: Electricity Connected; Sewer Connected; Water Connected View: Pool; Water Water Access: No Fixed Bridge; Ocean Access Water Source: Public Water View: Bay; Intracoastal Waterfront Features: Bayfront; Intracoastal; Navigable Water; Seawall Window Features: Storm Window(s) Showing Requirements: 24 Hour Notice; Call Listing Agent Outdoor Living Spaces: Patio Patio Details: Patio - Covered; Patio - Open Room Types: Dining Room; Kitchen; Living Room; Master Bedroom Acreage Description: 1/4 To Less Than 1/2 Acre Lot; Less Than 1 Acre Lot

Contract Information

Comp Sale YN
No
Original List Price
18500000
Occupant Type
Vacant
Listing Service
Full Service

Location and Legal

Country
United States
County Or Parish
Miami-Dade
Street Number
631
Street Direction Prefix
N
Street Name
Mashta
Street Suffix
Drive
Municipality Type
Incorporated
Municipal Code
24
State Or Province
FL
Postal Code
33149
Postal Code +4
1720
Subdivision Name
MASHTA ISLAND
Area
2520
Geographic Area
DADE
Elementary School
Key Biscayne K-8
Middle Or Junior School
Ponce De Leon
High School
Coral Gables
Special Assessment YN
No
Parcel Number
2452050080070
Zoning
2001
Flood Zone
AE

Financial Information

Application Required YN
No
Master Association YN
No
Membership Fee Required YN
No
Tax Annual Amount
112485
Tax Year
2025
Tax Legal Description
MASHTA ISLAND PB 60-93 LOT 7 BLK 1 LOT SIZE 100.000 X 150 OR 17980-3315 0198 4
Estimated Monthly Assoc Recurring Fee
0

Status Change Information

Major Change Timestamp
2026-07-30T18:40:51Z
Major Change Type
New Listing
Status Change Date
2026-07-30

More Information

Leasing Permitted Details

Leasing Permitted YN
No

Parking Information

Open Parking Spaces
6

Boat and Dock Information

Dock
Yes

Main Level Rooms

Main Level Bathrooms
4
Main Level Bedrooms
4

Pet Details

Pet Fee YN
No

Storm Protection

Impact Glass
Complete

Room Types

Dining Room Level
Main
Kitchen Level
Main
Living Room Level
Main
Master Bedroom Level
Main
Dining Room
Yes
Kitchen
Yes
Living Room
Yes
Master Bedroom
Yes

Price Calculations

Current Price To SqFt
8203.99

Originating Details

Originating System Key
20260729170810306019000000
Originating System ID
M00000170

Office/Member Information

DXORIGMLSID
RML

Dining Area

Dining/Living Room
Yes

Exterior Features

Garden
Yes
Private Rooftop Terrace
Yes

Flooring

Concrete
Yes
Laminate
Yes
Tile
Yes

Parking Features

Circular Driveway
Yes
Driveway
Yes
Attached Carport
Yes
Carport
Yes

Property Condition

Resale
Yes
Updated/Remodeled
Yes

Special Listing Conditions

Standard
Yes

Structure Type

House
Yes

Possession

Close Of Escrow
Yes
Negotiable
Yes

Sewer

Public Sewer
Yes

Utilities

Electricity Connected
Yes
Sewer Connected
Yes
Water Connected
Yes

View

Pool
Yes
Water
Yes

Heating

Central
Yes
Electric
Yes

Sprinkler Description

Auto Sprinkler
Yes
Zoned Sprinkler
Yes

Water Access

No Fixed Bridge
Yes
Ocean Access
Yes

Water View

Bay
Yes
Intracoastal
Yes

Window Features

Storm Window(s)
Yes

Appliances

Dishwasher
Yes
Dryer
Yes
Electric Cooktop
Yes
ENERGY STAR Qualified Dishwasher
Yes
ENERGY STAR Qualified Dryer
Yes
ENERGY STAR Qualified Freezer
Yes
ENERGY STAR Qualified Refrigerator
Yes
ENERGY STAR Qualified Washer
Yes
Free-Standing Freezer
Yes
Microwave
Yes
Oven
Yes
Refrigerator
Yes
Washer
Yes
Water Heater
Yes
Wine Refrigerator
Yes
Cooktop
Yes

Construction Materials

Brick
Yes
Concrete
Yes

Green Energy Efficient

Appliances
Yes
HVAC
Yes

Interior Features

Entrance Foyer
Yes
Walk-In Closet(s)
Yes

Laundry Features

Inside
Yes
Laundry Room
Yes
Sink
Yes

Listing Terms

Cash
Yes
Conventional
Yes

Pool Features

Equipment Included
Yes
In Ground
Yes

Roof

Shingle
Yes

Water Source

Public
Yes

Waterfront Features

Bayfront
Yes
Intracoastal
Yes
Navigable Water
Yes
Seawall
Yes

Water Heater Details

Electric Water Heater
Yes

Boat and Dock Features

Electric Available
Yes
Private Dock
Yes

Cooling

Central Air
Yes

Showing Requirements

24 Hour Notice
Yes
Call Listing Agent
Yes

Master Bedroom/Bath

Dual Sinks
Yes

Membership

No Membership Available
Yes

Pets Allowed YN

Yes
Yes

Pets Allowed

No Restrictions
Yes

Restrictions

See Remarks
Yes

Tax Information

City/County
Yes

Outdoor Living Spaces

Patio
Yes

Patio Details

Patio - Covered
Yes
Patio - Open
Yes

Acreage Description

1/4 To Less Than 1/2 Acre Lot
Yes
Less Than 1 Acre Lot
Yes

Room Information

Room Name Length Width Level
Living Room 16.00 22.00 Main
Kitchen 12.00 11.00 Main
Master Bedroom 25.00 20.00 Main
Dining Room 12.00 14.00 Main
IDX
Listing Office: Coldwell Banker
Last Updated: July - 30 - 2026
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