After the First World War, a dwindling congregation meant that, in 1923, Mrs Zoe Oakley Maund - later Lady Caillard - took the new lease of the building. She spent £4,000 to convert it into a private house with eight bedrooms, six fitted baths, and a new organ. The pews were removed to create an unusually charming private dining room, surmounted by a drawing room in the gallery. Known for her interest in spiritualism and the occult, Mrs Oakley Maund became famous for the séances she held at the Belfry in the early 1930s.
The Belfry was later acquired by Miss D M Lane, who became Mrs Wisher, and founded the Belfry Club jointly with her husband. Most of the early members were officers and ex-officers of the Royal Air Force. In 1954, The Belfry was sold to Mr Joseph Vecchi, a renowned restaurateur, who transformed it into a dining club.
Upon Mr Vecchi's death in 1961, the club was bought by Charles Winslow-Taylor on behalf of the owners of the Basil Street Hotel, who appointed Stephen Korany to run the club. During the 1970s, it was taken over by a group from the Middle East who undertook a lavish redecoration.