Following a period of building work, One Golden Square will be Bauer Media's London broadcast centre housing Magic, the Kiss brands, Planet Rock, the Absolute Radio brands, Kerrang and Heat radio.
Bauer Media is planning to build ten new studios, a new space from which to broadcast audio and video of live performances and a new reception area.
Steve Parkinson, the London managing director, Bauer Radio, said, "One Golden Square is an iconic radio location, known to the media industry and audiences alike.
"Having the national radio teams in one building will support our business objectives to drive initiatives and ideas across the Bauer Media group, and to build audiences and revenue."
With the addition of Absolute Radio, which it bought at the end of last year, Bauer Media's national radio stations reach more than 10 million listeners every week.