9 East 63rd Street is a 25-foot-wide brownstone built in 1879, offering exceptional scale, amazing natural light, and great ceiling heights on every level. The property presents a highly adaptable layout, ideally suited for conversion to a grand single-family residence.

Currently configured as a mixed-use property, there are two medical offices, one located in the basement and one on the ground floor. Above, the parlor level features a floor-through apartment with a rear extension and access to a large private terrace. The third and fourth floors are combined as a duplex, with expansive rooms, abundant light, and access to two private terraces. The fifth floor is a full-floor apartment with an efficient layout and an additional rear terrace.

With its impressive width, multiple outdoor spaces, and natural vertical flow, the property offers a rare opportunity to be transformed into a cohesive single-family townhouse with expansive entertaining levels and well-proportioned private quarters, all within a classic Upper East Side brownstone.