The building dates back to 1909 and was entirely residential until the Marriott group took over in 2002. It still retains its century-old facade.
The refurbishment will see a colour scheme of white, dove grey and lavender, with leathers, silk, solid wood and mirrored marble used throughout.
The revamp is part of a broader transformation of the north Mayfair neighbourhood as it prepares for the development of Crossrail, which will arrive in Bond Street in 2018.