Art collector Charles Saatchi is to move his gallery from London's South Bank to new premises in Chelsea.
The Gallery opened on London's South Bank in spring 2003
The gallery, which opened its doors at County Hall near Waterloo in 2003, is to move into the Duke of York's HQ building near Sloane Square in 2007.
Building work on the new 50,000 square foot space will commence in April 2006.
"It's a magnificent building and the very high footfall on the Kings Road makes it a perfect location," said gallery director Nigel Hirst.
"Taking this entire building in Chelsea will give the gallery the opportunity to grow and develop in a way that we would like."
"We are very sad to be leaving County Hall because in many respects it's been a great success," said Mr Saatchi.
"The Duke of York's HQ Building, which will give us extremely large, well-proportioned rooms with very high ceilings, will create a perfect gallery to look at contemporary art."
The 62-year-old collector has blamed the behaviour of his current landlord, Makota Okamoto, for his decision to move premises.
Mr Okamoto and his representatives could not be reached for comment on Tuesday.