The new offices would have the capacity for up to 3,000 employees
American Express has been given permission to build a new premises for its European headquarters in Brighton.
The credit card company will construct a new £140m development in Edward Street, behind its current base in the eight-storey Amex House.
As Brighton's largest private employer, American Express currently has more than 2,000 staff in the city.
Brighton and Hove City Council's planning committee voted unanimously in favour of the plans.
A council spokesperson said the development would "secure a future for Amex in the city" and bring £120m into the local economy each year.
The new offices would have the capacity for up to 3,000 employees.
A public consultation into the plans was held in October 2007 and the company announced its final proposal in September 2008 after three years of talks between American Express and the council.
The current site would eventually be demolished.