Whiteleys will become a 110-key hotel, complemented by a 3,500 sq m Six Senses Spa, and 14 branded residences for sale.
The department store was opened by draper William Whiteley in 1863.
Development of the hotel conversion is being done by a Meyer Bergman-advised fund, working with Finchatton. Complementing architectural addition by Foster+Partners are interiors by the highly admired AvroKO.
The project includes a 20-metre indoor swimming pool, and a wellness-social private members club.
Six Senses CEO Neil Jacobs is especially nostalgic about this project as he was brought up nearby and his parents used to bring him to Whiteleys to shop.