Greek Island Delays Put UK Summer Holidays on a Tight Clock

UK holidaymakers heading to Greece this summer have a practical reason to check their flight plans more closely: Greek airports ranked among Europe’s worst for long delays on routes back to the UK. Fresh analysis by AirAdvisor found that seven Greek holiday destinations were among the 20 European airports with the highest share of flights delayed by more than 60 minutes between June and September 2025. The warning lands just as Athens International Airport also faced disruption after an approach radar malfunction caused delays of up to two hours.

Behind the Headlines

The concern is not about one airport or one bad day. According to AirAdvisor’s flight disruption analysis, the research measured the proportion of flights delayed by 60 minutes or more on services between June and September 2025, a peak travel window for UK holidaymakers.

Greece stood out because several of its island airports are smaller hubs that can run close to full capacity in summer. That matters because once delays start, the impact can spread across the day: aircraft arrive late, departures are pushed back, and passengers on later flights can be caught in a knock-on delay even if their own flight was not the original problem.

The figures also show why the warning is especially relevant in Britain. Kefalonia recorded 11.79% of flights to UK airports delayed by more than 60 minutes, placing it third in the listed European ranking behind Milan Bergamo and Nice Cote d’Azur.

Here's What Happened

The AirAdvisor data placed Milan Bergamo first, with 11.96% of flights delayed by more than an hour, followed by Nice Cote d’Azur at 11.92%. Kefalonia was close behind at 11.79%, making it the highest-ranked Greek destination in the list.

Other Greek holiday routes also appeared high in the ranking: Corfu at 9.54%, Zakynthos at 8.48%, Chania at 8.33%, Kos at 7.72%, Rhodes at 7.68%, and Mykonos at 6.95%. For travellers, those percentages mean the risk is not evenly spread across Europe; several popular Greek island airports showed a higher rate of long delays than many other holiday destinations.

A separate disruption hit Athens International Airport when a malfunction affected one of the Civil Aviation Authority’s approach radars in the Merenda area. According to To Vima’s report on the radar failure, the issue affected the radar image used to monitor aircraft movements and caused some flight delays of up to two hours.

Authorities temporarily reduced the rate of arriving flights at Athens International Airport as a safety precaution while technical teams worked to restore the system. The restriction affected arrivals and departures, before the radar system’s operation was later restored.

Voices & Opinions

Anton Radchenko, CEO of AirAdvisor, said the data showed Greece was unusually exposed to disruption for UK passengers, especially on island routes where demand is intense during summer.

Our research found that Greece is by some distance the most disruption-prone country for UK air passengers.

Radchenko linked the pattern to airport size and seasonal pressure. Smaller airports can work efficiently in normal conditions, but when passenger volumes rise sharply and disruption begins, there is less room in the schedule to absorb the delay.

During the summer period, they frequently operate at maximum capacity, so that means that when a mass disruption event occurs, there are implications for other services.

The Bigger Picture

For UK travellers, the immediate effect is simple: leave more time around connecting journeys, transfers, ferry plans and hotel check-ins when flying to or from Greek island airports. A one-hour delay can be irritating; a delay that stretches beyond three hours can affect onward travel and may also trigger compensation rules.

The reports state that government rules may allow passengers to claim compensation if a flight is delayed by more than three hours or cancelled, with the amount depending on the delay length and flight distance. That does not mean every delayed passenger automatically receives payment, but it does mean travellers should keep booking details, boarding passes and delay notifications.

The Athens radar incident also shows how technical failures can quickly become passenger problems. Even when safety measures work as intended, limiting arrivals to keep operations secure reduces the number of aircraft that can move through an airport in a given period, which can push delays across departures as well.

The Road Ahead

The confirmed forward-looking point is that UK travellers with Greece holidays booked for the summer season should expect a higher risk of long delays than on many other European routes, particularly at smaller island airports listed in the disruption ranking.

Before travelling, passengers should check airline updates, airport notices and compensation rules if delays pass the three-hour mark.