Under Construction

343 Madison Ave

New York City · Office

Designed by Kohn Pedersen Fox and developed by BXP, the 844-foot-tall tower will bring 950,000 square feet of office space and a collection of tenant amenities.

Official Website
Last verified Jul 14, 2026
50%
AnnouncedBreaking GroundConstructionOpening SoonNow Open
07.29.25
Start
2029
Completion
46
Floors
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The story so far
Announced 2025 est.
Tenant announced Jul 2025Investment-grade financial-institution anchor signed LOI for ~274,000 SF (~30%)
bisnow.com
Broke ground Jul 29, 2025
Under construction
Expected opening Late 2029
Milestones are dated to when they actually happened and linked to their source. This record fills in over time as TMW tracks the project.
Developer & design
The New York City market 65 · Elevated supplyMidtown East 23-project pipeline · 7,801 residences and keys · peak Late ’28 Explore the market →
Common questions

Frequently asked

Where is 343 Madison Ave located?

343 Madison Ave is located in New York City.

When will 343 Madison Ave be completed?

343 Madison Ave is under construction, with completion expected in Late 2029.

Who is developing 343 Madison Ave?

Boston Properties is the developer behind 343 Madison Ave.

Who designed 343 Madison Ave?

343 Madison Ave was designed by Foster + Partners.

How big is 343 Madison Ave?

343 Madison Ave rises 46 stories.