Milton Coste

Licensed Real Estate Associate Broker

(917) 416-7433
6 W 20TH Street #2

For Sale · Listing by Serhant

6 W 20TH Street #2

Flatiron, Manhattan

$5,500,000

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Active For Sale • Co-op

$5,500,000

$1,250 per sq ft

6 W 20TH Street #2

Flatiron, Manhattan

The Greenwich Build

MLS® #RLS20118860

RLS at REBNY

Listing by Serhant

Open House Scheduled

Monday, October 5 • 5:00 PM – 6:30 PM

REBNY 2025: signed Buyer Representation Agreement required before any showing.

4
Bedrooms
3.5
Baths
4,400
Sq. Ft.
1907
Year Built

Quick Summary

Bedrooms 4
Bathrooms 4 full, 1 half
Living Area 4,400 sq ft
Year Built 1907
Ownership Co-op
Maintenance $8,670/mo
Neighborhood Flatiron
Floor 2 of 11

Property Highlights

  • Views: City
  • Outdoor Space: Terrace
  • Style: Loft architecture

Property Details

Type Co-op
Ownership Stock Cooperative
Total Rooms 8
Baths 3 Full, 1 Half
Floor 2 of 11
View City
Cooling Other
Pets Yes
Year Built 1907
Living Area 4,400 sq ft
Architectural Style Loft
Basement Other
Parcel # 0821-0049-00006-000-0000002
Block/Lot 00821/0049

Listing History

Event Date Price Change
Listed Oct 2, 2026 $5,500,000 -
Currently Oct 2, 2026 $5,500,000 -

Description

Opportunities like this rarely come up in Flatiron. Unit 2 at 6 West 20th Street is a full-floor loft of approximately 4,100 square feet in The Greenwich Building, a 1907 Schwartz & Gross landmark in the heart of the Ladies' Mile Historic District. Here is the chance to buy a true full-floor loft in one of Manhattan's most sought-after neighborhoods, renovate it to your exact taste, and build significant value along the way. The loft already has a working kitchen and 1.5 baths. The rest is a vast, open space ready for your vision. Soaring 14-foot ceilings and giant original pivot windows fill the floor with north and south light, giving the space the volume and character that define classic pre-war loft living. With about 50 feet of frontage and a deep, regular floor plate, the layout can easily fit four bedrooms plus a home office, alongside generous living and dining space and a great room built for entertaining. The loft also has approximately 300 square feet of private outdoor space, a rare feature for a full-floor home in Flatiron. Picture morning coffee, summer dinners, or a planted garden retreat right off your living space. Bring your contractor and architect to build your dream home. With the floor wide open, you can design your home almost from scratch, from the number of bedrooms to every finish. Wet-over-dry layouts are permitted, giving you real freedom to place kitchens and bathrooms where they work best for your plan rather than where the building dictates. The upside is clear. A recently renovated full floor with the same footprint in this building is currently offered at $8,500,000 (without outdoor space). Buyers who want to create a custom home and build substantial equity at the same time will be hard pressed to find a better starting point in downtown Manhattan. The unit is currently approved for commercial use, however, the co-op board has confirmed it supports converting the unit to residential and is actively encouraging it, following the many floors above that have already made the change. This is a well-established path in the building, not an exception. The Greenwich Building is a boutique, 11-story neo-Renaissance co-op with a striking landmarked facade and only a handful of homes. Residents enjoy keyed elevator access to their floor, two elevators, a ButterflyMX virtual doorman, and a pet-friendly policy. Set just off Fifth Avenue on one of Flatiron's prettiest blocks, the building puts you steps from Madison Square Park, Union Square and its Greenmarket, Eataly, and some of the city's best restaurants and shops. A Citi Bike dock sits right across the street, and the subway lines at 23rd Street and Union Square are a short walk away. Buy it, renovate it, and build your dream home, with real value built in from day one. Several images have been virtually rendered. This unit requires a renovation.

Features & Amenities

Interior Features

Dining Area High Ceilings Building None

Exterior Features

Private Outdoor Space Under60 Sqft Terrace

Building Information

Financial Details

Maintenance $8,670/mo

The Flatiron District is a busy intersection of history, technology, and luxury living. Named after the iconic Flatiron Building, the neighborhood is centered around Madison Square Park and is a hub for the city's 'Silicon Alley.' The real estate market is famous for its grand cast-iron loft buildings with high ceilings and expansive floor plans, alongside ultra-luxury glass towers that offer modern amenities and central Manhattan convenience.

Flatiron Live Market Data

View Neighborhood

Active Listings

114

Median Asking Price

$2.74M

Median $/Sqft

$1,896

Avg Days on Market

N/A

New This Week

6

Price Reduced

25%

Sold (30 Days)

17

Median Sale Price

$1.95M

Live data from RLS at REBNY • Updated 10/2/26, 3:45 PM EST

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Location

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6 W 20TH Street #2, Flatiron, New York County

Virtual Tour

Floor Plans

Floor Plan 1
Floor Plan 2

Building Information

Official NYC property records for this building

M1-5M
Zoning District

Tax & Assessment

Assessed Value: $1,228,950
Land Value: $1,228,950
Exemptions: $1,228,950

Note: Individual unit taxes may differ. Verify current tax bills with NYC DOF.

Lot Area: 4,600 SF

Source: NYC PLUTO (Primary Land Use Tax Lot Output), NYC Department of City Planning (data.cityofnewyork.us)

Want help estimating ownership costs or understanding building compliance? Let's discuss

Frequently Asked Questions

Common questions about this property

The current listed monthly maintenance are $8,670 per month. Confirm the exact amount with Milton Coste before making an offer.

This property has 4 bedrooms and 3 full bathrooms and 1 half bathroom.

The listed interior living area is 4,400 square feet. Verify dimensions independently during due diligence.

According to MLS records, the building was constructed in 1907, making it approximately 119 years old.

This listing is a co-op (stock cooperative). Buyers purchase shares in a corporation rather than real property, and the board must approve all sales.

Pets are permitted at this property: Pets Allowed,Building Pets Allowed Comments:Pets Allowed. Contact Milton Coste for weight limits or breed restrictions.

At the current list price of $5,500,000 for 4,400 sq ft, the asking price per square foot is approximately $1,250. This figure is for reference only and may differ from appraised or assessed values.

To schedule a private showing, contact Milton Coste at (917) 416-7433 or milton@miltoncoste.com. Per REBNY guidelines effective 2025, a Buyer Representation Agreement is required before a buyer's broker can show you properties. You may attend open houses independently without one.

Have a question not answered here?

(917) 416-7433
MLS® ID: RLS20118860
First Listed: 10/2/2026
On Market: 10/2/2026
Price Changed: 10/2/2026
Contract Date: 10/2/2026

Listing Courtesy of Serhant - Corrin Thomas

Listing Contact: (212) 495-9871

Listing information for certain New York City properties provided courtesy of the Real Estate Board of New York's Residential Listing Service (the "RLS"). The information contained in this listing has not been verified by the RLS and should be verified by the consumer. The listing information provided here is for the consumer's personal, non-commercial use. Retransmission, redistribution or copying of this listing information is strictly prohibited except in connection with a consumer's consideration of the purchase and/or sale of an individual property. This listing information is not verified for authenticity or accuracy and is not guaranteed and may not reflect all real estate activity in the market. ©2026 The Real Estate Board of New York, Inc., all rights reserved. This advertisement does not suggest that the broker has a listing in this property or properties or that any property is currently available.

Broker Commission Disclosure: Broker commissions are not set by law and are fully negotiable.

Buyer Notice: Planning to work with a buyer's broker? A Buyer Representation Agreement is required before your broker can show you properties, per REBNY/UCBA guidelines (effective 2025). You may attend open houses independently without one.

RLS at REBNY

RLS Data display by Keller Williams NYC. Data last updated on 10/2/2026 at 7:45 PM UTC

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Milton Coste - NYC Real Estate Broker

Milton Coste

Licensed Real Estate Associate Broker

Keller Williams NYC

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Sale history, taxes, violations and comps for this unit

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Flatiron Market Update

17 sales last 30 days · $2.74M median · 6.7 months supply

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Quick Facts

Status Active Type Co-op Neighborhood Flatiron Borough Manhattan
County New York
Floor 2 of 11
Year Built 1907
First Listed 10/2/2026
Style Loft
Living Area 4,400 sqft
Maintenance $8,670/mo

Monthly Costs Estimate

Down Payment 20%

$1,100,000

Interest Rate Loading...

Source: Freddie Mac PMMS

Loan Term 30 years

Est. Monthly Payment

$0

Principal & Interest $0
PMI (under 20% down) $0
Maintenance $8,670
Total Monthly $0

Estimates only. Consult a lender for exact figures.

Mansion tax applies at this price point

New York State charges the buyer a mansion tax on residential purchases at $1,000,000 or more. At this asking price the tier is $5M to $9,999,999 at 2.25%, applied to the whole purchase price. It is due in cash at closing and cannot be financed.

Estimated mansion tax at asking

$123,750

Run the numbers on a different offer price

Estimate based on the asking price. Confirm your own obligation with your real estate attorney.

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