About 20,000 prospective holidaymakers are stuck with no holiday after their travel agent, Golden Sun, went bust.
The sun has set on the Golden Sun Group
Another 10,000 holidaymakers could be stranded abroad until they can make alternative arrangements to get home.
Golden Sun currently has 10,500 customers on holiday in Greece, Cyprus, Portugal and Croatia.
The 20,000 customers with forward bookings should get money back from the Civil Aviation Authority (CAA), paid out of an industry insurance fund.
About 2,500 travellers were due to fly out this weekend alone.
The failure of the medium-sized travel company is the biggest "for some time", a CAA spokesman said.
Golden Sun has been struggling to meet its liabilities, the Association of British Travel Agents (Abta) said.
"We started to get complaints from hotels that had not been paid by Golden Sun over a year ago," said Frances Tuke of Abta.
Golden Sun customers should be flown home as normal, using cover provided by the CAA's Air Travel Organisers' Licensing (Atol) system, the organisation said.
Holidaymakers are usually well protected when tour operators go bust, it added.
The CAA said no-one has ever been left stranded in a situation like this.
People who were due to go on holiday can either get a refund from CAA, or they can go to a travel agent and exchange their refund for a different holiday.
This is essentially funded through Golden Sun's £9.8m bond with the Atol system.
The Atol system provides protection for the 28 million people who travel from Britain with tour operators each year.
Alternatively those who booked their holiday using a credit card will usually find their purchase was insured.
Left to pick up the bill
Those currently awaiting news of their return flight may be feeling less optimistic.
One holidaymaker stranded in Greece said that he cannot leave his hotel because the bill has not yet been paid by Golden Sun.
"Some new guests who arrived last night had to pay for the hotel again, so they are using their spending money to get accommodation," Jim White from Tavistock told the BBC.
"There is some concern that we might get stuck here, it's the unknown which is the problem," he said.
However a CAA spokesman said: "We will ensure all holidaymakers are brought home as planned and we are contacting hoteliers, to ensure them that we will pay their costs."
BBC News Online readers tell us their experiences with Golden Sun
My sister and brother -in-law own a small hotel in Perama Corfu (The Perama Hotel)and have been devastated by Golden Sun who owe them in excess of £20k sterling. They have not received any monies for last year holidays let alone this year and have been working in excess of 20 hours per day, 7 days a week through the end of last summer and the whole of this summer. This company have sent them cheques which have not been honoured by the bank and for months have been making false promises. Is there anything I can do to help my family? It's very difficult for them to help themselves from Corfu as any contact details they have seem now to be useless.
Terry Hodges, Wakefield, West Yorks
Flew out to Corfu in August, did not receive my baggage when i arrived for a two week holiday. treated really bad by staff, no explanations. am waiting for some kind of compensation and explanations from golden sun for my ruined holiday. What happens now? never received my baggage!
CHRISTINA LITTLE, Bedford, uk
Having spent the whole summer working in Kos as a Courier for Golden Sun it would have been nice to have been paid!! Presumably I shall be low down the list when it comes to settling creditors.
Lindsey Chapman, Kardemena, Kos
My wife and i have been travelling with Golden Sun for a number of years to Corfu Greece, and to the same accommodation.
This year when we arrived in June the owner who we know complained to us that she was upset because she had not been paid for 2003and that she was considering closing the apartments, i mentioned this to the rep and she denied that this was the case.
Four days into the holiday we arrived back at our rooms to find that all the guests had been asked to leave by the owner, Golden Sun offered us alternative accommodation which was very poor, i rented alternative accommodation for the rest of the holiday at my own expense, Golden Sun still denied that there was a problem, but rumours were rife in the resort among the Greeks.
When we arrived back in the UK i wrote to Golden Sun asking to be reimbursed the 350 Euros that i had spent on accommodation but they admitted they were completely to blame but refused to pay even after 6 weeks they still would not admit that there was a problem with them not paying the accommodation owners.
Randal Carey, Keston, Kent
I was meant to be going to Rhodes with golden sun on wed 29th Sept but got a call from my travel agents on Friday to say we had lost the holiday, luckily we've rebooked another holiday. I'm just glad it happened before we went, it must be terrible for the people stuck out there!
Rachael collier, Bridgend, Mid Glamorgan
we travelled to Greece on 26/8/2004 with golden sun, when we arrived at our apartments the owner would not allow us in has he said he had not been paid for the accommodation by golden sun, we were left standing outside the apartments for two and half hours in the blistering sun of lunchtime. the rep was useless and made no contact with us whatsoever, when asked what was happening he just kept saying he didn't know. eventually we were allowed into the apartments but no apologies came from golden sun.
steph devey, yelverton devon
We booked with Golden sun for two weeks in Crete this September and had our passports held by the hotel owner because he was owed 120,000 euros by golden sun. He would not give people their passports back and we were all worried about getting home.
Lara Darbyshire, Lincoln UK
We had big issues at our hotel complex in Chania, Crete, regarding unpaid monies of £124,000 owed to our hotelier. We were informed during our holiday that we would not be receiving our passports back until Golden Sun paid some of the debt owed to the hotel. Various holidaymakers got involved making phone calls to Golden Sun Head Office and also to the British Consulate etc. The hotelier did receive £20,000 due to help received by the guests. However Golden Sun were most unhelpful to us at the time. This issue caused us immense distress as we were left wondering whether we would be able to get home or not.
Miss Michelle Gregory, Lincoln, Lincolnshire