BT Group has announced more than 4,000 of its staff will be working out of a new office in Birmingham, as it becomes the latest company to base major operations in the city.
Staff will occupy the majority of floors in the new 17-storey Three Snowhill building.
West Midlands mayor Andy Street said it showed companies "see a profitable future in the West Midlands".
Workers will move in to the building from the end of the year.
Graeme Paton from BT said it would become a "strategic hub location" for the company in the UK and would see five times the current number of its staff working in the city.
In February last year, HSBC opened its new headquarters in Birmingham with 2,000 members of staff.
Mr Street said it was another "major company" moving into the West Midlands and meant BT would become one of Birmingham's biggest employers.
He said the Snow Hill area alone was now home to the likes of HS2 Ltd, KMPG, Barclays, and law firm Gowling.
"I am delighted that a firm of BT's size and stature has made this move, and it shows just how far our region has come in recent years that the UK's biggest companies now see a profitable future in the West Midlands," Mr Street said.
Paul Faulkner, chief executive of Greater Birmingham Chambers of Commerce, added: "This is a further sign not only of Birmingham's renaissance but also the growing confidence that exists within the city's business community at present."
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