According to the campaigning group, the airlines owe more than £4.5m and the current system was fundamentally flawed in passenger protection rules, with many people taking legal action via country court orders.
"The scale of court judgments piling up against major airlines is a result of a system where the odds are stacked against passengers and airlines feel empowered to routinely ignore their legal obligations to pay out refunds and compensation." Said Rocio Concha of Which?.
The Guardian newspaper reports that Wizz Air is responsible for the total amount owed, according to the consumer group’s analysis of the Registry Trust, which is a record of court documents and fines in England and Wales.