Pegging your holiday hopes on the promises of fledgling airlines or tour operators is a one-way ticket to disappointment, if the recent experience of Irish consumers is anything to go by.

JetGreen completed the journey from buzzing start-up airline advertising cheap deals to collapsed fly-by-night operator in record time this month, following in the wake of FreshAer last summer and JetMagic in January.

JetGreen's nosedive left hundreds of travellers stranded in Spain and ruined the plans of many more who were due to travel.

Passengers who have paid for cancelled flights are advised to contact their credit card company, travel insurer or travel agent. If they are unable to secure a refund from these sources, they can make a claim to the Commission for Aviation Regulation. As a licensed tour operator, JetGreen held a bond with the commission, which is now being used to refund customers.

Claim forms available from the commission must be returned with appropriate documentation by mid-July (within 60 days of the date it ceased trading).

FreshAer had yet to receive its licence as a tour operator when it collapsed and, although it refunded customers, the incident prompted the commission to warn consumers to check that their travel agent or tour operator was properly licensed.

But the protection offered by the commission does not extend to flights originating abroad. Anyone who booked a flight from Spain to Dublin cannot seek a refund from the commission.

Consumers who booked other services such as accommodation or car hire through JetGreen's website will not receive a refund for deposits paid, as these services are not covered by the bond.

In the case of the Cork-based airline JetMagic, customers who did not book by credit card and did not have insurance had to join the queue of creditors of a firm estimated to be €3.5 million in debt.

Under a process known as "chargeback", however, credit card issuers must refund customers who have paid for goods or services using their card in the event the seller of the goods or services fails to deliver.

Travel insurance will not always provide cover for the cost of cancellation or making alternative travel arrangements when a tour operator, airline or other firm becomes insolvent or is unable to meet their obligations.

This may be listed under "general exclusions" in the terms and conditions of some policies.