Mount Sinai OB-GYN Groups Relocate to 7K SF at 348 Amsterdam Avenue

Two Mount Sinai obstetrics and gynecology faculty practice groups are relocating to 348 Amsterdam Avenue on Manhattan’s Upper West Side.

The 7,000-square-foot space sits below Related Companies’ 18-story condominium building the Harrison, which rises 145 feet and comprises 125 units, according to a recent certificate of occupancy.

The practice groups plan to move there from their previous location about a block and a half away at 50 West 77th Street, between Central Park West and Columbus Avenue, West Side Rag reported. The future medical office was formerly a retail space for sporting goods store Modell’s, which closed its location there in 2020.

The two groups will begin accepting patients at the practice in June, a representative told Commercial Observer.  

The length of the new lease is unknown, and Mount Sinai did not disclose the asking rent for the property. The neighborhood’s average asking rent in the nearby retail corridor along Broadway from West 72nd to West 86th streets was $247 per square foot at the end of 2025, according to a report from CBRE. A recent analysis of office rents set Manhattan’s average price per square foot at  $78.48 in February.

The space is undergoing a gut renovation, a Mount Sinai representative told West Side Rag, and will be ready in June. The space features new equipment and will offer obstetrics, gynecology, minimally invasive surgery and midwifery care.

The practice groups’ doctors and midwives will perform deliveries and surgeries at Mount Sinai West, located between West 58th and 59th streets at 1000 10th Avenue.

Newmark’s Benjamin Birnbaum and Andrew Taub appear to have represented the landlord, according to signs affixed to the building. It is unclear whether Mount Sinai worked with a broker.

Birnbaum and Taub did not respond to requests for comment. 

Emily Davis can be reached at edavis@commercialobserver.com.