M&S moved out of the property during last summer and autumn, relocating to a modern open-plan site in Paddington Basin.
The move was hailed by the retailer as the critical step to adopting a new, more open way of working. 'It was difficult to have open communication at our old building. We wanted to put in new technology which would solve that problem and that wasn't really possible there,' said a spokesperson.
M&S put the property up for sale in September last year with a price tag of£110, through commercial agent Jones Lang LaSalle. Bidders for the property were understood to include Heron, Development Securities and British Land.
The sale to London and Regional will be completed within the next three months.