44 Union Square East Office Space (Tammany Hall Building)

Finding office space in New York that doesn’t feel like a compromise is tough. You want character but you also need modern systems that work. You want a good address but not at the cost of everything else. 44 Union Square East office space is one of those rare finds that delivers on both fronts.

The Building’s Got History and More

The story starts in 1928 when this place went up as Tammany Hall, designed by Thompson, Holmes & Converse and Charles B. Meyers for the Tammany Society. Fast forward to 2013 and the New York City Landmarks Preservation Commission made it official with landmark status. So yes, you’re working in a piece of actual New York history at 100 East 17th Street. That said, Reading International, the current owner, completely transformed this place in a 2020 redevelopment with BKSK Architects. They added three full floors to what was originally a three-story building, and the project earned an AIA design award. More importantly for you and your team, they replaced everything that needed replacing: infrastructure, mechanical systems, heating, cooling, the works.

Your Space Can Work the Way You Need It To

Here’s the practical part that matters for your day-to-day operations. 44 Union Square East office space spans roughly 74,000 square feet of Class B space across six floors, with floorplates ranging from 4,444 to 15,058 square feet. That range means something important—you’re not forcing your team into a layout that almost works. Need a smaller floor for a tight-knit team? You’ve got it. Growing fast and need something bigger? That’s available too. The landlord keeps things flexible, open to full-building tenants, multi-floor setups, or mixing retail and office, whichever makes sense for your business. What really changes the game here is that tortoise shell-shaped dome covering the fifth and sixth floors. Natural light pours through it down to the fourth floor, which means your team works in bright, energizing spaces.

The Amenities Solve Real Problems

You’re not just renting square footage at 44 Union Square East office space. You’re getting a building that supports how your team works every day with strong amenities.

• Climate Control: The new HVAC systems keep every floor comfortable without the cold spots, hot spots, and constant thermostat battles that can make people miserable.
• Sunlight That Changes Everything: That distinctive dome isn’t for show—it brings natural light into your workspace, which means happier employees, lower energy bills, and spaces people enjoy working at.
• Infrastructure You Can Count On: Brand new mechanical and electrical systems mean your internet stays up, your power stays on, and your IT team can focus on your business.
• Visibility for Your Brand: Signage opportunities facing Union Square put your company name in front of thousands of people daily, helping clients find you and giving your brand the exposure that usually costs a fortune.
• Layouts That Bend to Your Needs: With floorplates from 4,444 to 15,058 square feet, you can design the exact mix of open areas, private offices, meeting rooms, and collaboration spaces your team actually needs.

Getting to Work Made Simple

Your commute matters, and so does your team’s. 44 Union Square East sits just steps from Union Square in the heart of Midtown South, with multiple subway stations nearby on 23rd Street, 14th Street, and Third Avenue. Your employees can choose from multiple train lines, cutting down commute times from across the city. The location also means lunch breaks and after-work plans happen within walking distance, with countless dining options, shops, and entertainment venues surrounding the building. Clients visiting your office will find you easily accessible from any part of Manhattan, and the Union Square address immediately signals that you’re positioned where business happens.

You’ll Fit Right In

Choosing 44 Union Square East office space means you don’t have to settle. The landmark designation and architectural character draw businesses that want their workspace to reflect something about their identity and values. The range of floor sizes accommodates everyone. Creative agencies building their teams. Tech companies scaling up. Professional services firms needing flexibility. And so on and so forth. Anyone that values both form and function will find themselves at home.