18, Cavendish Square W1

No 18 Cavendish Square is a terraced house built in the 1770s, with alterations made in the mid-19th century. It features a brown brick exterior and a slate roof, standing three storeys tall with a basement and a mansard roof that includes dormers. The ground floor is adorned with rusticated stucco, while a bracketed stone cornice and blocking course complete the top. The house has three windows on the first floor, which are framed by 19th-century stucco architraves with dentilled alternating pediments, and it boasts cast iron balconettes from around 1800. The entrance is similar to that of No 17.

Inside, the house has notable features including a staircase that rises to the full height of the building, illuminated from above, and a "Chinese" wrought iron balustrade. There are mahogany doors and architrave doorcases throughout. The first-floor drawing room is particularly impressive, featuring a fine statuary marble "console" chimneypiece and exquisite Rococo stucco work on the ceiling, which includes a central oval with putti, roundels depicting reliefs from Lafontaine's Fables, and intricately modeled birds. The ceiling of the first-floor rear room displays a more restrained Rococo design and also includes an original marble chimneypiece.