Compensation is due at three hours or more, measured on arrival.
Check your flightThree hours is the threshold, and it is measured by when you arrived, not when you took off. This is not written in the regulation itself. It comes from the Court of Justice decision in Sturgeon, which held that passengers arriving three hours or more late suffer the same loss as passengers whose flight was cancelled, and should be treated the same way.
Arrival time is defined as the moment at least one aircraft door opens and passengers are permitted to leave. Not touchdown, and not the time the airline logged for its own on-time statistics. That distinction decides borderline claims.
The amount depends only on distance, not on how late you were beyond the three hour mark. A three hour delay and a nine hour delay on the same route pay the same.
Under three hours, no compensation is due, though a delay of two hours or more still entitles you to meals and drinks at the airport.
Compensation is a flat amount set by distance, not by ticket price: €250 up to 1,500 km, €400 for longer flights inside the EU and for 1,500–3,500 km, and €600 beyond 3,500 km. The UK equivalents are £220, £350 and £520.
Distance is measured in a straight line from your original departure airport to your final destination, which on a connecting itinerary often lands you in a higher band than you would expect.
Duty of care is separate from compensation and does not depend on the cause. Once you are delayed two hours or more the airline owes you meals and drinks, two phone calls, and a hotel plus transfers if you are stuck overnight. This applies in bad weather, during ATC strikes, and in every other situation where no compensation is payable.
Airlines frequently provide none of this during major disruption. Buy your own, keep every receipt, and claim the cost back afterwards.
Work out what you are owed