The Royal Bank of Scotland is to move into Land Securities' Bankside 2 and Bankside 3 buildings on Southwark Street.
Land Securities has exchanged contracts with the Royal Bank of Scotland for the pre-letting of the Bankside 2&3 development.
RBS will take a 20 year lease occupying a total of 377,910 sq ft over the two buildings, with rental levels of £46.50 for the best space.
Bankside 1, now known as the Blue Fin Building, is occupied by IPC Media following its sale in May 2004.
"Our decision to build Bankside 123 was based on our belief that the Bankside area has always held the potential to be a diverse and exciting location for commercial, retail and residential users," says Mike Hussey of Land Securities.
"Royal Bank of Scotland now joins IPC Media at our Bankside complex along with a strong list of retailers. Tate Modern is expanding and new residential schemes are adding to the area's attractiveness.
"We are delighted that RBS have recognised that in their commitment to the scheme and look forward to welcoming them into their new offices."
Bankside 3 will include a community office/events space with access from Great Guildford Street.