Administrators for online book seller The Book People have confirmed more than 150 redundancies at the Bangor site after a buyer was not found.
The company went into administration on December 17th last year and the corporate finance team PwC was hired as its administrator.
On Friday, PwC confirmed 155 workers have been made redundant.
The company operated from its head office in Surrey and co-ordinated its deliveries from a 92,000 square foot warehouse in Bangor.
The reason for the business going into administration was given as being because of a "difficult trading environment that the business had been experiencing, combined with increasing working capital pressures".
Administrators say The Book People will continue to trade through its E-commerce channel with the retained staff and its intention is to fulfil all customer orders received and accepted.
The Book People, which was founded by Ted Smart and Seni Glaister in 1988, has an annual turnover of more than £50 million and employs 393 staff across the UK.
Administrators PwC had said in December that the company, owned by private equity firm Endless since 2014, was exploring a sale and that it not expect any immediate job losses.
Retail giants like Amazon dominate the online book market. The Book People had make 76% of their profit from online sales.