Utilities utilitywise has gone into administration and has endangered 1,000 jobs.
The company, which helps business customers buy gas and electricity, said it was unable to raise enough cash to cover its debt.
A plan to sell the company had failed.
The collapse of UtilityWise (UTW) comes after a recent bailout by founder of Newcastle-based Geoffrey Thompson.
Last month, it turned out that it took £ 10 million to keep its business alive after encountering "unexpected challenges and old problems".
After the company did not receive shareholder participation, it went on sale at the end of January.
However, a statement on Wednesday's website states that the formal sales process announced by the board "did not produce any offers".
"The UTW directors therefore sought the appointment of administrators."
The company has hired FTI Consulting to complete the administration process, saying that its energy brokerage business would stop trading immediately.
However, the other subsidiaries will continue to trade while looking for buyers for those parts of the group.
Mr. Thompson, who retired from the board two years ago, built UTW from a bedroom in South Shields into a multi-million pound AIM listed company.
According to a Sunday Telegraph report, the company had recently warned employees that it could not guarantee that they could be paid in March.