Rail minister Lord Adonis described the acquisitions as “a major step forward” for the delivery of the £16 billion Crossrail scheme.
The buildings, which were first named in the Crossrail Bill in 2005, are to be demolished for the major project. Tottenham Court Road will be redeveloped, with the Tube ticket hall to be extended to six times its current size in order to handle the new train services.
The station revamp is part of a series of multi-million pound contracts for work on the central London section of the scheme.
All six Tube stations on the route, including Paddington, Liverpool Street and Bond Street, will be revamped as part of the overall project.
The £400 million contract for the project delivery partner role on the 21 km of twin-bored tunnels from Paddington through to Stratford and Custom House is expected to be announced before the end of the year.
Balfour Beatty is working with US firm Parson Brinckerhoff in an attempt to secure the work. US firms Bechtel and Flour are also bidding, as is Laing O'Rourke.
While early construction works will begin next year, major work on the tunnels will start in 2010 with plans for completion by 2017.