Allied London has secured accountant PwC as the 50,000 sq ft pre-let anchor tenant within No.1 Spinningfields in Manchester.
Currently under construction, the 20-storey office on the site of Quay House will be around 340,000 sq ft and is set to complete in spring 2017.
PwC exchanged contracts yesterday for the fifth and sixth floors, and will relocate its 750-strong team to Spinningfields in summer 2017.
PwC is currently based in Barbirolli Square.
No.1 Spinningfields is designed by SimpsonHaugh & Partners, and includes eight retail and leisure units which according to Allied London are under offer to international operators with the exception of two small kiosk units.
Iwan Griffiths, PwC's North West chairman, said: "The North West continues to be an area of focus and investment for the firm, and we are very proud to be anchoring this iconic Manchester development.
"No. 1 Spinningfields will provide our people with a first class working environment, enabling us to continue to attract the top talent so we can best serve our clients and help them achieve their objectives."
Mike Ingall, chief executive of Allied London, said: "We want this building to be a very sustainable development not just environmentally but commercially. We have placed a variety of communal spaces within the tower, including a roof top restaurant. The garden, which will be located at level 21 is going to be an amazing place, and 12,000 sq ft of real space to entertain and enjoy. The corporate venue on the seventh floor will also be a first, a very simple box designed where events can take place and where companies can take over the space for an hour, a day or a week, to help shape their business.
"At level 3 we will also have a large fully serviced business lounge, similar to that found at international airports. This space has been created to have a relaxed but considered feel and where meetings can take place 'out of the office'."
The letting agent is OBI. Patrick Joynson at Savills advised PwC.