Private equity giant Blackstone has committed to a new 225K SF headquarters in Mayfair’s Berkeley Square.

The firm will move from its 75K SF base at 40 Berkeley Square into a redevelopment of Lansdowne House, 57 Berkeley Square, which is to be overhauled by its owner, the Brunei Investment Authority. Blackstone will take the entirety of the building.

According to React News Blackstone is mooted to have set a move-in date of 2028.

The new office will see the private equity giant more than triple the number of workers it has in London from around 600 people to up to 2,000 staff.

It is understood that rents on Lansdowne House have reached £200 per SF in the last few years, with Blackstone looking to negotiate a long-term lease for the revamped 10-storey property, which has been redesigned by architect AHMM.

Once complete it will include 225K SF of offices as well as 14K SF of retail and restaurant space. The retail units have been designed to attract smaller retailers.

According to the architect, the current building is constrained by an “inefficient layout of multiple structural cores, compounded by low floor to ceiling heights".

The redeveloped property will have a larger floorspace, enhanced floor-to-ceiling heights to maximise daylight into the building and a restoration of an original “garden pavilion”.

AHMM said that the redesign would “create a new building that better respects the character and history of the area”.