SL Green and Mori Building Advance New 46-Story Madison Avenue Tower

• SL Green Realty Corp. and Mori Building Co. are moving forward with a new 46-story office tower at 346 Madison Avenue.
• Demolition is expected to begin in the third quarter of 2026, with completion targeted for 2031.
• The 850,000-square-foot project will feature extensive amenities, wellness facilities, hospitality offerings, and outdoor spaces.

What the Project Includes

A major new office tower is set to reshape Midtown Manhattan as SL Green and Mori Building Co. prepare to begin redevelopment of the former Brooks Brothers property at 346 Madison Avenue. The joint venture plans to replace the existing buildings with an approximately 850,000-square-foot office tower designed to compete with the newest generation of trophy office developments emerging around Grand Central Terminal. Demolition is expected to commence later this year, allowing construction to move forward on one of Manhattan’s most closely watched office projects.

What Makes the Tower Stand Out

According to project details released by the development team, the building is being positioned as one of New York City’s most amenity-rich office properties. Plans include multiple floors featuring terraces and loggias, a luxury wellness center, an indoor padel court, a 215-seat auditorium, hospitality-focused tenant spaces, and landscaped outdoor areas overlooking Madison Avenue. The project reflects the continued evolution of premium office development, where lifestyle amenities have become a major competitive advantage in attracting tenants.

What This Means for Midtown Manhattan

The development arrives amid a broader transformation of the Grand Central and Madison Avenue corridor. Major projects, including One Vanderbilt, JP Morgan Chase’s new headquarters, and additional office developments along Madison Avenue, have helped reposition the area as one of Manhattan’s most desirable business districts. Developers continue investing heavily in premium office environments as tenants increasingly seek newer buildings that offer advanced amenities, sustainability features, and proximity to major transportation infrastructure.

What the Design Team Brings

The tower is being designed by Kohn Pedersen Fox (KPF), one of the world's leading architects of high-profile office towers and mixed-use developments. While renderings have not yet been released, the firm's involvement signals an emphasis on design quality, workplace innovation, and skyline impact. The project is expected to become a prominent addition to the Madison Avenue corridor once completed.

What the Industry Will Watch Next

Attention will now shift to demolition activities and the eventual release of architectural renderings. Leasing activity will also be closely monitored as developers position the building within Manhattan’s evolving office market. As premium office properties continue outperforming older buildings, the success of the Madison Avenue project could further reinforce the trend toward large-scale trophy office development in New York City.