The number of tour operators going under has increased this year and more holiday company collapses could follow, according to the Civil Aviation Authority (CAA).
Most tourists going overseas are protected from a company failure as they are with firms that operate under the CAA's Air Travel Organisers' Licensing (ATOL) bonding scheme.
The CAA said that although holiday bookings for summer 2008 had held up well, there had been an increase in the number of ATOL-holder failures in the first four months of this financial year.