Law firm Bott and Co said its research showed Tui Airways and easyJet were among the worst offenders for not settling compensation payouts until court proceedings had been issued by customers.

The firm’s research revealed that Tui only settled 29% of compensation claims before the start of legal action, while this figure was 55% for easyJet and 56% for Virgin Atlantic.

The best airlines for paying passenger compensation quickly were Thomas Cook (89% of claims paid before court proceedings), British Airways (90%) and Jet2 (91%), according to Bott and Co.

Coby Benson, flight delay solicitor at Bott and Co, said: “If the airlines were fully complying with the law then 100% of payouts would be without court proceedings.

“We understand that airlines need to look at claims on an individual basis; however what we’re seeing is airlines routinely defending claims for eligible flights, some where they’ve already paid dozens of others on the same flight.”

A report by the European Court of Auditors published earlier this month found that airline passengers had to “fight hard” to secure the compensation they were entitled to.

The auditors have recommended improving the process for consumers including automatic compensation for delays “in certain situations” so they do not have to claim for themselves.