Notices have appeared on the shop doors of Quartz Travel in Heworth Road and Quartz Travel Lite in Blossom Street (formerly Amigo Travel), advising that the premises are closed.
A spokesperson for insolvency practitioner Begbies Traynor has confirmed the closure (on Wednesday August 30) to TTG today, and Quartz Travel’s website is down.
The company, which was founded by entrepreneur Paul Smith in 2004, employed 13 staff in York.
The Begbies Traynor spokesperson said: "Begbies Traynor in York has been instructed to assist the director of the business in seeking the appointment of administrators and a notice of intention to appoint administrators has been filed at court. Once appointed, the administrators will explore the potential sale of the business and assets.
"The company’s financial difficulties have arisen from a dispute with its managed services provider, through which holidays were booked, and resultant court proceedings.
"The company’s director has confirmed that holidays booked through Quartz Travel remain protected by Abta and Atol and that all relevant information is included in customers’ booking documentation."
A message on Quartz Travel’s answering machine says that the company is closed due to "unforeseen circumstances".
It advises that people with bookings made before July 10 should call a number which diverts to its former consortium, Freedom Travel Group.
A spokesman for Thomas Cook, which owns Freedom Travel Group, told the York Press: "I can tell you that we have been forced to terminate Quartz Travel’s contract as a Freedom Travel member.
"All its customers that booked before July 10 have been contacted by us to advise them that their holidays are safe. Those that booked later will have protection through Atol.
"So everyone who has booked a holiday can rest assured that all is fine."