Phoebe Gates’ Startup Phia Inks Leases at Flatiron Building

Phoebe Gates’ fast-growing AI shopping startup has found a new home in the Flatiron District.

Phia, the AI-powered price comparison platform founded by Microsoft co-founder Bill Gates’ youngest daughter and her Stanford classmate Sophia Kianni, signed a lease for the 8,900-square-foot penthouse at 37 East 18th Street, The Real Deal has learned.

The length of the lease and asking rent at the newly redeveloped office building owned by Zar Property NY were not known. Zar was represented in-house and JLL represented Phia. Zar declined to comment and JLL did not immediately respond to a request for comment.

The lease comes days after Phia announced it had raised $35.5 million in fresh funding, bringing the company’s total haul to $43.5 million, according to People magazine. The latest round attracted a roster of celebrity investors, including Khloé Kardashian, Alix Earle, Paris Hilton and Jessica Alba.

Launched in April 2025, Phia helps shoppers compare prices across retailers, estimate resale values, track price drops and identify lower-cost alternatives. The company now boasts more than 1.5 million users and has partnerships with more than 9,600 retail brands, People reported.

The Zar family acquired the 67,000-square-foot office property for $27 million in 2024 and recently completed a full-scale renovation that included a new lobby and rooftop designed by BKSK Architects. The project repositioned the century-old building as a boutique Class A office property a block from Union Square.

Phia joins a wave of AI companies snapping up office space in New York. AI tenants accounted for more than a third of the tech sector’s demand in the first quarter of 2026 with 670,000 square feet leased, according to Colliers, a sharp jump from its 12 percent share in 2025.

Phia did not immediately respond to an e-mail request for comment.