The bank warned some of its IT contractors that they may not have been paid for September and October and advised them to contact the agency, Munroe Systems, which went into receivership on 30 October.
One worker told Computer Weekly he was owed about £10,000 for work completed in September and October. Another, who contacted the receivers Smith & Williamson, was told the contractors were "highly unlikely" to be paid.
To compound matters, two days after the contractors found out the company had gone bankrupt, BNP Paribas said it was cutting payments to its contractors by 10%.
"It sounds really messy, but this is the kind of financial risk my members face all the time," said Jane Akshar, chairman of the Professional Contractors Group.
The receivers and BNP Paribas refused to comment.