With summer approaching, late flights are still an issue across Europe.

In its latest annual report, pan-European air traffic management coordinator Eurocontrol urged airports and airlines to tackle system congestion ahead of the summer peak, as air traffic continues to soar, with total flights now at 100.2% of pre-pandemic levels.

In 2025, Lisbon, Zurich, and Nice topped the list for delayed departures, with the Portuguese capital also ranking among the worst-affected airports for late arrivals, alongside Athens and Luxembourg.

How late are flight departures at Europe’s top 20 airports?

Lisbon’s Humberto Delgado had a particularly rough 2025, with one of the sharpest drops in departure punctuality.

The rate of planes leaving on time fell to 49%, the lowest rate not only among Europe’s top 20 busiest hubs, but across the entire continent.

What are the most punctual airports in Europe?

While many passengers are quick to point the finger at the airport authorities, the Eurocontrol study suggests that a number of reasons are to blame for the delays.

The agency said that Lisbon’s take-off operations were severely hampered by adverse weather conditions, “en-route restrictions causing traffic bunching at airports”, and several airports operating at near full capacity with little operational buffering.

Nevertheless, some airports in Europe appear to deal with these issues better than others.

At the other end of the table, the Norwegian cities of Bergen and Oslo, Sweden’s Stockholm, Denmark’s Copenhagen and Germany’s Lipsia led the way for the number of flights taking off on time, all with a punctuality rate surpassing 80% at departure.

When it comes to which airports have improved the most in this regard, Munich, Rome Fiumicino and London Heathrow showed the greatest gains.

Why do flights depart late?

Knock-on delays accumulated across the aviation network, also called reactionary delays, continued to be the main cause of disruption, costing an average of 6.5 minutes per flight, which is why flying in the morning is preferable to evening departures.

But how common are these delays? According to Eurocontrol, a staggering 30% of aeroplanes experience late takeoffs, with an average delay of 15 minutes.

Despite a 4% improvement in punctuality, the organisation stressed that, to keep up with growing traffic in the coming months and years, authorities must tackle the shortage of air traffic controllers, improve airspace design and route planning, and accelerate technological innovation.

Which are the busiest airlines and airports?

Istanbul’s IGA Airport handled the highest number of flights in 2025 in the Eurocontrol monitored network, with 1,491 flights per day on average, followed by Amsterdam Schiphol (1,351), London Heathrow (1,315) and Paris Charles de Gaulle (1,314).

All of Europe’s top 20 airports, except London Gatwick, saw their air traffic rise between 2024 and 2025 — particularly Istanbul Sabiha Gökçen, with a double-digit growth (+13.8%) compared to an average +4.3% in Europe.

The continent’s network saw around 30,000 flights per day — 35,000 during the May —August peak season.

When it comes to airlines, Ryanair was the busiest, operating almost 3,192 flights a day, followed by EasyJet with 1,611, and Turkish trailing closely at 1,559, ahead of Germany’s flag carrier Lufthansa (1,083) and France’s Air France (1,061).