Microsoft is planning a revamp of its 500-acre headquarters in Redmond in Washington state, where it has been based for the past 30 years.
The extension will add 18 buildings, 622,450 sq m of renovated workspace, $150m in transportation infrastructure, as well as more green space.
Amenities include a 2-acre plaza that can accommodate 12,000 people, walking trails, facilities for football and cricket and retail space.
The development will add space for 8,000 more staff to the 47,000 who work on the campus.
The project will create around 2,500 construction and development jobs.
The new campus is described by Microsoft as "more open and less formal, divided into a series of ‘team neighbourhoods'".
The company also plan to build a pedestrian bridge to connect the campus to the Redmond Technology Transit Station, which will be completed in 2023.
The project will take five to seven years to finish.
Apple’s $5bn, 175-acre Cupertino campus opened in April this year.
Image courtesy of Microsoft