A group of people using a former car showroom as a squat have been given until Monday to leave.
About 20 people moved in to building on Iffley Road in Oxford on New Year's Eve.
Leaseholder Midcounties Co-operative said it had been granted a repossession order last month, but told the squatters they could stay until April.
But owner Wadham College, which is turning the site into student flats, said it needs the building back.
A spokesman for the Iffley Open House campaign group said: "It has been a great space - something that was desperately needed - it has helped quite a few of the people better themselves.
"We've got somebody going off to university. One of the residents has been housed."
Kevin Brown, group general manager at Midcounties Co-operative, previously said the company had a legal obligation to hand the site back to Wadham College in April.
He said the firm been granted a repossession order but "our preference is not to have to use it".
Wadham College, which is part of Oxford University, said it had "deep sympathy" for the homeless people but the development could not be delayed.