How much you are owed for a delayed or cancelled flight
The European rules give you up to 600 euros when you land three hours late, and most people never claim it. Here you see whether you qualify, how much, and you get the claim letter already written to send to the airline: no middleman keeping 25 to 35 per cent.
When it applies, and how much
The rule is Regulation (EC) 261/2004, which covers every flight leaving a European airport (whatever the airline) and flights arriving in Europe on a European airline; leaving the UK, the British copy of the same rules applies, with the amounts in pounds. The amounts depend on the great-circle distance between the two airports, not on the ticket price: €250 up to 1,500 km, €400 up to 3,500 km or for flights inside the Union, €600 beyond 3,500 km outside the Union. The delay is counted on arrival, not on departure, and the threshold is three hours: that was set by the Court of Justice, not by the airline.
«Technical fault» and «strike» are not the same thing
They are the two most common answers used to avoid paying, and they are exactly the ones the Court of Justice rejected. A technical fault is the normal risk of the business and does not remove your right (Case C-549/07, Wallentin-Hermann); nor does a strike by the airline's own staff, because that is its own organisation (Case C-195/17, Krüsemann). Bad weather, an air traffic control strike, a bird strike or a medical emergency on board are extraordinary circumstances. And if nobody tells you anything, that is not your problem: the airline has to prove it.
What you get even when compensation is not due
In bad weather compensation is not due, but care is, and hardly anyone asks for it: drinks and meals after two, three or four hours of waiting depending on distance, two phone calls, and a hotel with transfers if you have to stay the night. If the flight is cancelled you choose between a refund within seven days and another flight to the same destination; if the delay passes five hours you get that choice anyway. And compensation does not remove your right to further damages you can prove.
The letter, and why you do not need an agency
The companies that handle these claims keep 25 to 35 per cent, and what they do is send a letter. Here the letter comes out written, with the route, the calculated distance, the amount and the articles quoted: copy it, add your booking reference and bank details, and send it to the airline. Watch out for vouchers: the regulation says compensation is paid in money, and vouchers can only be accepted with your written agreement (Article 7(3)). If nobody answers within six weeks, take the complaint to the national body (the CAA in the UK).
Do not wait, and what this page does not do
The regulation does not say by when you have to claim: national law does, and it varies a lot - six years in England and Wales, five in Scotland and Spain, three in Germany. If in doubt, move within the first year. This page does a calculation and writes a letter: it is not legal advice and it contacts nobody for you. On distance and thresholds it does not slip; on the facts (the real arrival time, the reason for the delay) whoever holds the evidence decides. If you just need the distance between two cities there is Distance between cities.