Heathrow has lost its position as Europe’s busiest airport after Istanbul Airport moved ahead in July 2026, handling about 8.15 million passengers against Heathrow’s 7.85 million to 7.9 million. The London hub linked the reversal to its long-running expansion debate, saying the case for adding capacity has never been clearer.
The monthly ranking shift was driven by contrasting summer traffic trends. Heathrow’s passenger total fell 1.5% year on year, while Istanbul’s rose 2.3%, leaving the Turkish hub ahead by roughly 300,000 travellers. Heathrow’s busiest day of the year came on 19 July, when it handled 267,000 passengers.
The result is significant because it reflects a monthly comparison rather than a full-year ranking. Heathrow finished 2025 narrowly ahead of Istanbul overall, but July’s figures underline how quickly the balance among Europe’s major hubs can change during the peak travel season.