If you’ve ever been on a delayed flight, you’ll know how frustrating it is – whether you’re waiting in the cramped airport lounge for an update, or on a stuffy plane grounded on the runway. 

Delays are a pretty common experience. London Stansted was the worst UK airport for flight delays last year, a Press Association analysis has found – with departures being an average of 25 minutes late. 

Birmingham and London Luton recorded the joint second worst punctuality performance, with aircraft typically taking off 19 minutes behind schedule.

So if your flight is delayed, what should you do?

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You have rights under EU law if you’re travelling from the UK or on a European airline – but in most instances, these won’t kick in until the delay is over two hours, or, for long-haul flights, four hours, according to Citizens Advice.

Depending on the length of the delay, you may be entitled to access what airlines call “assistance” – such as free phone calls, food, and accommodation (if you are delayed overnight) – or monetary compensation if the delay is longer. 

It’s all a bit complicated, because what you’re entitled to depends on the length of the delay and the length of the flight. 

Here’s a rundown:

You will qualify for assistance if: 

You have travelled less than 932 miles, say from London to Paris, and your flight is delayed by two hours.

You have travelled between up to 2,175 miles and your flight is delayed by three hours. 

You have travelled over 2,175 miles and your flight is delayed by four hours.

The rules are different when it comes to compensation.

Your flight will need to arrive at its destination three hours late or more, according to Which? – as long as the delay was not caused by an extraordinary circumstance outside of the airline’s control including security risk, political instability or severe weather that makes flying dangerous.

You will qualify for compensation if:

You have travelled less than 932 miles and are delayed more than three hours – €250 

You have travelled up to 2,175 miles and are delayed more than three hours – €400 

You have travelled over 2,175 miles and your flight is delayed between three and four hours – €300

You have travelled over 2,175 miles and your flight is delayed by more than four hours – €600

For more information on flight delays and how to claim compensation, visit Citizen’s Advice.