Revealed: 20 flights you should avoid in 2025

Which? Travel has found that Ryanair’s Teesside to Palma route and Corendon Airlines’ London Gatwick to Antalya route are the worst for long flight delays. While trips departing from Manchester airport accounted for five of the worst 10 routes with delays of more than one hour in 2024.

We analysed Civil Aviation Authority (CAA) airline punctuality and cancellation statistics from January 2024 to October 2024, which showed that Corendon Airline's flight to Antalya in Turkey and Ryanair’s route to Palma, Mallorca, were delayed by more than an hour 37% of the time.

Worse than a delay is a flight that doesn’t take off at all. Our analysis found five of the 10 worst routes for cancellations within 24 hours of departure departed or landed in Scotland or its Isles, which is partially a reflection of difficult weather conditions.

But more than 10% of British Airways flights from London Gatwick to New York JFK were also cancelled within 24 hours of departure, suggesting you might want to pick a different route for your next trip to the Big Apple.

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Worst flight routes for delays of more than one hour

Are there alternative route options to avoid the worst delays?

There will usually be an option to fly with a different airline on the most popular routes at larger airports.

On the London Gatwick to Antalya route, you could opt to fly with Turkish Airlines instead of Corendon. Just one in 10 of this airline's flights were delayed for over an hour (compared with Corendon’s almost four in 10 and Freebird Airlines’ three in 10).

Alternatively, you could swap to a nearby airport. There are no alternatives to Ryanair’s Teesside to Palma route, but you could choose to depart from Newcastle airport instead and fly with Tui, delayed over an hour just 2% of the time.

We asked Ryanair, easyJet and Corendon Airlines if they wanted to comment on our findings. We didn’t hear back.

Freebird Airlines, however, pointed out to Which? that while our reference period is from January to October, it only operates a daily service on this route from late May until early November. It flagged that the period between January and April has far fewer flights and less congested airspace, meaning that our dataset will favour airlines operating throughout the entire period.

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Why are so many routes from Manchester delayed? 

Of the top 10 worst routes for delays over an hour, Manchester was the departure airport for five of them, our CAA data analysis shows.

The routes are:

• Manchester to Bodrum, Turkey (Jet2)
• Manchester to Zagreb, Croatia (Ryanair)
• Manchester to Kos, Greece (Jet2)
• Manchester to Dhaka, India (Biman Bangladesh Airlines)
• Manchester to Chania, Greece (Jet2)

Manchester airport told Which?: ‘Passengers travelling from Manchester airport can feel assured that the vast majority of our flights – 76% since April last year – leave on time. Ryanair and Jet2.com are two of our most popular airlines and have good punctuality rates overall.

‘There is a huge range of factors that can affect the punctuality of flights and are outside an airport’s control, including weather, airline crew shortages, delays to inbound flights and air traffic control issues like airspace restrictions and even industrial action.

‘All the routes referenced departed from Manchester later in the day, between 4.30pm and 8.55pm, having operated flights elsewhere earlier in the day, meaning they are more vulnerable to delays.

‘We are working closely with airline partners and air traffic controllers in the UK and abroad to improve the punctuality of the routes listed, as well as others that are affected by delays.’

See how Manchester airport scored in our survey of the best and worst airports

Why are there long delays on flights to Turkey?

Delays are likely due to the Ukraine war and congested flight corridors to Turkey and beyond to the Middle and Far East.

Worst routes for late cancellations

Our analysis of CAA data revealed that between January and October 2024, one in three of Air China’s Gatwick to Beijing flights was cancelled (with less than 24 hours' notice), making it the worst route for last-minute cancellations.

However, this isn’t the only route that travellers should be wary of.

Aberdeen to Humberside and Aberdeen to Wick John O’Groats routes, run by Eastern Airways, were cancelled one in five times (with less than 24 hours' notice) in 2024 (Jan-Oct).

The latter route is subsidised by the Highland Council and the Scottish government because it connects residents to essential services and opportunities in larger cities.

In October last year, Eastern Airways admitted that its subsidised service’s reliability had fallen short due to operational issues and adverse weather and agreed to implement new measures to improve it.

What happens if my flight is cancelled or delayed?

If you’re due to fly with a UK or EU-based airline, or you're departing from a UK or EU airport, you’re protected under the Denied Boarding Regulation. Your airline must help if your flight is cancelled or delayed.

Depending on how long you are delayed and why, you could be entitled to a refund or alternative flight, food, phone calls, accommodation and potentially flight cancellation compensation. For full details, see our guide on flight cancellation and delay compensation. 

Research notes: We excluded flight paths that flew fewer than 44 times in the Jan to Oct 2024 period (as this is fewer than 20% of average flight paths flown). We excluded flight paths that no longer exist in 2025. We considered just scheduled departure flights, not chartered. Cancelled flights are defined as the non-operation of a previously planned flight announced less than 24 hours before or after its scheduled departure time.

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