Sainsbury's is considering leaving its Holborn HQ and moving outside London, as it seeks to cut costs and transform its business culture.
A move could enable Sainsbury's to halve its rent. The grocer moved into Holborn in 2001, paying a reported£54.75 per sq ft (£589 per sq m) - representing£16.4 million on 300,000 sq ft (27,870 sq m).
The grocer has reduced head office staff by 20 per cent in the past 18 months. Numbers at Holborn stand at 3,000 compared with 4,000 who moved from Stamford Street.
Job cuts have meant that some parts of the distinctive glass building - a legacy of the high-spending Sir Peter Davis era - now lie empty, and Sainsbury's bosses are understood to be keen to move to a less flashy building with a lower rent.
New chief Justin King is also keen to instil a more go-getting, customer-focused ethos and make a break with the past.
One source said: 'It's likely that Sainsbury's will move, but it could take a couple of years.'
A move outside London is one option being examined. Rival Tesco has become a global retail force from its functional head office in unglamorous Cheshunt.
Property specialist Chris Hiatt of Jones Lang LaSalle said office space in locations such as Croydon and Watford costs between£20 and£25 per sq ft.
A Sainsbury's spokeswoman did not deny a departure from Holborn is being considered, but said: 'No decision has been made. We will not comment on speculation.'
Sainsbury's signed a 25-year lease on Holborn and may need to sub-let or reassign the property.