Branches of Warehouse, Oasis and Coast could close after the brands are auctioned off to a new owner.
Potential new owners include turnaround firms Alteri and Endless, according to The Telegraph, raising concerns that shops will be shut down to save money.
The package of High Street labels was put up for sale in November by its administrators for its owner Kaupthing, a failed Icelandic bank.
As many as 5,000 are thought to be employed by the three brands, which share a head office in Shoreditch.
Karen Millen, which is also owned by Kaupthing’s administrators, has also been tipped for sale.
Spokespeople for PwC, which is handling the sale, Kaupthing and Alteri declined to comment. Endless did not respond to requests for comment.