Istanbul Overtakes London Heathrow as World's Best-Connected Hub

Istanbul Airport now tops the ranking of the world's best-connected aviation hubs, displacing London Heathrow, according to the aviation data provider OAG. The ranking uses the company's Connectivity Index, which counts the possible connecting itineraries at each airport on the busiest day of the year, 2 August for 2026. A connection must have no more than six hours between landing and onward departure, and at least one of the two flights must be international. That number is divided by the number of destinations served.

Istanbul offers links to 337 destinations and reached an index value of 265.4. Turkish Airlines accounts for 80 percent of capacity at the airport. The hub moved up from second place in 2025.

London Heathrow falls from first to second, with an index of 246.2. Its number of possible connections dropped six percent from the previous year. British Airways is the largest carrier at Heathrow, with 51 percent of capacity.

Amsterdam Schiphol remains third. Frankfurt stays in the top ten but fell three places.

OAG publishes the connectivity ranking each September. Unlike the better-known lists of the world's busiest airports by passenger numbers, the index measures transfer options rather than traveler throughput. The passenger ranking is led by Atlanta, which handled around 106 million travelers in 2025, followed by Dubai International and Tokyo Haneda.