The collapsed holiday firm Travelscope has been sold to its former managers.
When the Gloucester-based company went bust with the loss of more than 200 jobs in December, about 45,000 customers were affected.
The firm blamed litigation over a cancelled cruise as the reason for going into administration.
Bristol-based Phoenix Holidays, set up by former Travelscope managers, has bought the company but 12,000 holidays have been cancelled.
Paul Clark, from the administrators Menzies Corporate Restructuring (MCR), said: "It has unfortunately been necessary to cancel approximately 12,000 passenger holidays, covering all holidays with departure dates between 22 December 2007 and 31 January 2008.
"However I hope that Phoenix Holidays can now assist the remaining passengers with either fulfilling their holidays or offering them an alternative holiday of similar standard."
Phoenix Holidays has been set up by Darren Parris and Anu Desai, former managers with the failed Travelscope.
"This announcement means that a large number of Travelscope passengers who have booked a coach holiday or a river cruise can have their holidays fulfilled, and these passengers can look forward to their holiday with renewed peace of mind," said Mr Parris.
"In the immediate term, however, Phoenix will not be offering any holidays by air and therefore passengers who have booked flight holidays with Travelscope will need to complete a claim form with the Civil Aviation Authority."