According to a comprehensive statistical report by AirAdvisor, a leading platform defending air passenger rights, Humberto Delgado Airport in Lisbon recorded a 6.74% rate of flights with severe delays, surpassed on a European scale only by the hubs of London Heathrow, Frankfurt, and Milan Malpensa.

On the affected connections in the Portuguese capital, the average delay was 88 minutes, nearly doubling from the previous year's rate of 3.34%.

Francisco Sá Carneiro Airport in Porto follows this worsening trend, with a 4.25% serious delay rate and the highest average wait in the country at 102 minutes.

At the top of the European ranking compiled by the consultancy firm, which audited 18 major airports on the continent, is London Heathrow with a delay rate of 6.26% and average waiting times of 126 minutes. Close behind are Madrid Barajas (6.29%) and Barcelona El Prat (5.25%), both showing significant increases in delays compared to the previous period.

Technical analysis attributes this wave of disruptions and mass cancellations, especially on short-haul continental routes, to cost pressures created by the direct financial impact of the Middle East geopolitical crisis. Since the start of 2026, these factors have doubled aviation fuel prices, causing airlines to experience their highest cost pressure since the peak of the Ukraine crisis in 2022 and resulting in network bottlenecks.

Departures from Lisbon and connections to Barcelona, as well as the air bridge to Porto, exhibit severe delay rates of 15.6% and 10.8%, respectively. Lisbon's systemic bottleneck is further evidenced by connections to Portela among the three most problematic routes from major airports, affecting 10.8% of departures from Heathrow, 8.9% from Malpensa, and 5.6% from Frankfurt.

Total flight cancellations tripled in Porto, rising from 0.28% to 0.90% out of 23,000 flights, while Lisbon ranked 15th in Europe with a cancellation rate of 0.64% across more than 66,000 operations.

Anton Radchenko, CEO of AirAdvisor, attributes these figures to budget and low-cost carriers' operational decisions amid high fuel prices, which have led them to cut short-haul routes where fuel costs are unsustainable. In contrast, Nordic and Central European airports, such as Stockholm Arlanda, Warsaw Chopin, and Helsinki Vantaa, stood out for their performance.

In response to airlines’ attempts to invoke the energy crisis as an extraordinary circumstance to avoid costs, the European Commission's Directorate-General for Mobility and Transport issued formal guidelines. These guidelines clarify that airlines’ decisions to cancel flights or impose retroactive surcharges due to regular market risks, such as fuel price volatility, do not exempt them from responsibility.

Therefore, passengers affected by cancelled flights or delays exceeding three hours retain all rights under EU Regulation No. 261/2004, including refunds, rerouting, and financial compensation of up to €600, with airlines prohibited from charging retroactive surcharges.

Special attention is given to sensitive island routes without direct same-day alternatives, such as the connection between Lisbon and Ponta Delgada in the Azores, where the carrier is legally obligated to provide immediate assistance with accommodation and meals due to the lack of
alternatives for stranded travellers.