Virtual TourMap

For SaleSingle Family ResidenceActive

520 S Mashta Dr

Key Biscayne, FL 33149

$18,500,000

94 Days On Site

  • 5Beds
  • 4Baths4 full
  • 3,085Sq Ft
  • $5,997Per Sq Ft
  • 0.5083Acres
  • 1961Built
Subdivision
Mashta Island A Replat Of
County
Miami-Dade
MLS®
A12071221

Overview

Seize a rare opportunity to create a landmark waterfront estate on one of the largest residential lots in Key Biscayne’s exclusive Mashta Island enclave. Spanning an extraordinary 22,140 square feet, this exceptional property offers 138 feet of pristine water frontage and sweeping open water views, providing an unparalleled setting for a world class residence. Plans by renowned architect, Pablo Corazzini of Vitalini Corazzini Architects, are available to the buyer, offering a thoughtfully conceived vision that takes full advantage of the property’s remarkable scale, premier waterfront setting, and spectacular sunsets. The proposed design creates an extraordinary canvas for sophisticated indoor-outdoor living and entertaining, should the buyer choose to pursue the concept. With its exceptional lot size, expansive water frontage, and coveted Mashta Island address, this is a truly irreplaceable opportunity to create a legacy estate in one of South Florida’s most prestigious waterfront communities.

Listing Snapshot

Price
$18,500,000
Days On Site
94 Days
Bedrooms
5
Inside Area (SqFt)
3,085 sqft
Total Baths
4
Full Baths
4
Partial Baths
0
Lot Size
0.5083 Acres
Year Built
1961
MLS® Number
A12071221
Status
Active
Property Tax
$201,741 (2026)
HOA/Condo/Coop Fees
N/A
Sq Ft Source
N/A

Property Details

General Features

11 items
Direction Faces
East
Disclosures
None
Garage
Yes
Garage Spaces
2
Parking
Driveway
Property Sub Type
Single Family Residence
Sewer
Public Sewer
SqFt Total
4,177
Style
OneStory
Water Source
Public
Zoning
2001

Interior Features

5 items
Appliances
Other
Cooling
Central Air
Flooring
Tile
Heating
Central
Interior
Master Downstairs

Exterior Features

10 items
Construction Details
Block
Frontage
138
Lot Features
Waterfront
Pool Features
In Ground, Private
Private Pool
Yes
Roof
Barrel, Spanish Tile
View
Bay, Ocean
Waterfront
Yes
Waterfront Features
Ocean Access, Seawall
Waterview
Bay, Ocean

Community Features

3 items
Community Features
Other
MLS Area
52
Financing Terms Available
Cash, Conventional

Location

520 S Mashta Dr, Key Biscayne, FL 33149 · 52

Neighborhood & Commute

ZIP Code 33149

Median household income
$152,895
Income per person
$72,459
Households
5,812
Average household size
2.75
Median age
41.6

Source: Walk Score.

Disclosure: Community information and market data powered by Constellation Data Labs. Information is deemed reliable but not guaranteed.

Schools

Elementary School
Keybiscayne
Middle School
Ponce De Leon
High School
Coral Gables

Price & Status History

  1. Listing updated with changes from the MLS®
  2. Price changed to $18,500,000
  3. Status changed to Active
  4. Listing first seen on site

Friends & Family

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Listing courtesy of Coldwell Banker Realty (305) 798-3124

Stellar MLS

Listing information is provided by Participants of the Stellar MLS. IDX information is provided exclusively for personal, non-commercial use, and may not be used for any purpose other than to identify prospective properties consumers may be interested in purchasing. Information is deemed reliable but not guaranteed. Properties displayed may be listed or sold by various participants in the MLS Copyright 2026, Stellar MLS.

Last checked: 2026-11-14 01:04 AM EST

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