One Madison Logo

1 Madison Avenue, New York, NY

Adding to a thriving neighborhood, SL Green is proud to announce the redevelopment of One Madison Avenue, a marquee building that will set the standard for new office construction in the sub-district.

One Madison will create 18 additional column-free floors above the existing building – expanding the rentable space to nearly 1.5 million square feet. The renovation will also include terraces on the 10th and 11th floors, featuring exceptional views of Madison Square Park and the surrounding area, in addition to private tenant terraces at the top of the tower. The building’s lobby and ground-floor retail space will undergo a full upgrade, too.

One Madison was built as part of the Metropolitan Life Insurance Company’s original campus which includes the iconic MetLife tower -- the tallest building in the world when it was built in 1909. When completed, the campus was an international sensation in the architectural community, not only for its modern design, but also for the complex’s rapid construction. In 1953, One Madison was renovated as a late Art Moderne building to reflect the contemporary style. SL Green’s plans for One Madison will literally build upon this history and continue the building’s legacy as an iconic address for the new century.

“Transforming One Madison into a preeminent office building will further establish the Flatiron District as the top destination for some of the most creative and distinguished companies in the world,” said Kurt Cavanaugh, Deputy Director of the Flatiron 23rd Street Partnership. “We’re excited to welcome One Madison’s new tenants to New York’s most dynamic neighborhood that includes the city’s top restaurants, retail environment and access to several subway and bus stops.”

Part of the area’s appeal is Madison Square Park, a beautiful, historic public space that hosted the first baseball game in 1842 and produced the original, world-renowned Shake Shack. Beyond the Park, the district is home to over 200 restaurants, bars, and casual options. This includes the Michelin-star restaurant Eleven Madison Park and Eataly, the widely popular Italian marketplace. In total, more than 560 ground-floor businesses, more than two-thirds of which are locally owned and independent, call the neighborhood home. The area is also a hub for fitness and wellness centers, boasting an incredible 47 gyms and studios.

Through attracting preeminent firms and retailers while implementing a stunning design, the amplified One Madison will accentuate the neighborhood's best qualities. The building’s tenants will feel at home with incredible amenities in a thriving neighborhood. Through this project, SL Green is ensuring Midtown South remains the most sought-after business district in the world.

Contact Information

Leasing Agents

David M. Kaufman
Senior Vice President
SL Green Realty Corp.
(212) 356-4104
Paul Glickman
Vice Chairman
Jones Lang LaSalle
(212) 418-2646
Diana Biasotti
Senior Vice President
Jones Lang LaSalle
(212) 812-5751
Alexander Chudnoff
Executive Managing Director
Jones Lang LaSalle
(212) 418-2622
Benjamin Bass
Vice President
Jones Lang LaSalle
(212) 812-6026

Property Management

Kevin Reade
VP, Portfolio Manager
SL Green Realty Corp.
(212) 216-1663


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