Primark will anchor the transformation of Barton Square at the centre which will gain another 110,000 sq ft of retail space, a new glass-domed roof and a refreshed interior.
Construction work on the site is due to start in the first half of next year and complete in 2019.
Colin Flinn, regional managing director for intu, said: “This is a significant milestone for intu Trafford Centre that will enable us to reposition and redevelop an important part of the centre so that we can create even better customer experiences and more opportunities for retailers to flourish.
“The work we are planning at Barton Square will attract more visitors for longer by expanding the centre’s retail and leisure mix and creating a new space befitting this architecturally-rich building.”