Istanbul overtakes Heathrow: What makes an airport a hub
OAG ranks Istanbul first for 2026 for the first time. What counts is the interplay of network, schedule and capacity – with a clear lesson for Zurich.
Istanbul has overtaken London Heathrow in the ranking of the world's best-connected major airports. The aviation data provider OAG places Istanbul Airport in first place for the first time in its 2026 edition: the connectivity index stands at 265.4 points, with Heathrow following at 246.2. Frankfurt ranks seventh, three places lower than a year earlier.
The finding is more than a prestige success. It explains how a hub comes about – and why, in the debate about Swiss and Lufthansa, Switzerland must distinguish between the public interest in good connectivity and the commercial responsibility of a private airline.
The ranking measures the transfer schedule
For its Megahubs, OAG evaluates possible transfer connections, not simply the number of passengers or destinations. The 2026 edition is based on the schedule for Sunday, 2 August 2026, one of the busiest days of the year. What matters is how many connections can be combined within reasonable transfer times and how large the seat capacity behind them is.
The top position therefore says neither that Istanbul is automatically the most pleasant airport nor that it generates the greatest economic benefit. It shows rather that arrivals and departures are coordinated particularly tightly. Especially for passengers transferring between Europe, Africa, Asia and the Middle East, for instance, many individual flights become a network.
Network, frequency and available capacity
According to OAG, Istanbul serves 337 destinations within twelve months. Turkish Airlines provides around 80 percent of the capacity there. This strong position of a network airline makes coordination easier: feeders land in waves, long-haul flights depart in the waves that follow. According to OAG, the airport can use three runways simultaneously. That creates room to manoeuvre when many connections have to be handled within a short time.
The strategy does not rest on the location between continents alone. Turkish Airlines reports a network of 356 airports in 132 countries for the end of 2025. A large network, however, only yields many usable connections once aircraft, gates, ground handling and schedule are aligned. Heathrow also lost ground in the OAG comparison because its possible connections on the reference day fell by six percent compared with the previous year; OAG points, among other things, to lower capacity to the Middle East.
A hotspot creates access, but no automatic formula for prosperity
A functioning hub can make it easier for companies to reach markets, strengthen tourism and secure air freight links. It bundles demand so that long-haul routes become possible that would not be economically viable with passengers from the immediate catchment area alone. Travellers benefit as well, because connections can be offered more frequently or more directly.
The benefit comes at a price, though: more noise, land requirements, emissions and conflicts over operating hours. Moreover, a large airport does not automatically produce a successful economic policy. What remains decisive is the reliability of operations, good rail and road connections, competitive costs and a flight offering that is genuinely relevant for companies and residents.
What Switzerland can influence at Swiss and Lufthansa
Zurich is considerably smaller than Istanbul, yet its function is similarly important for Switzerland. The Federal Office of Civil Aviation notes that bundling local and transfer demand is what can make regular intercontinental flights economically viable in the first place. That applies in particular to an export-oriented economy with many international business ties.
The federal government, the canton and the airport can influence the framework conditions: infrastructure, security and environmental requirements, operating hours, air traffic agreements and the airport's link to public transport. They can also ensure that Zurich has competitive conditions as a hub.
The concrete product design, by contrast, remains a corporate matter. Swiss is part of the Lufthansa Group; business class on short- and medium-haul routes, menus, fares, seat concept and individual routes are not decided by the Federal Council. They are decisions of the airline and its group, shaped by competition, demand, costs and brand. Political influence over a better onboard meal would therefore be the wrong lever. What matters more are reliable processes, sufficient connecting options and functioning access to the airport.
The lesson from Istanbul is not a copying manual
Istanbul shows how quickly an airport gains weight when infrastructure and a dominant network airline are geared towards transfers over years. For Zurich, this does not mean pursuing size at any price. Switzerland can only maintain and develop its smaller hub if it remains fast, plannable and reliable for passengers and airlines – within clear environmental and noise limits.
The OAG ranking is therefore less a verdict on national airlines than a reminder of the logic of a hub: it is not the individual flight that decides, but the connection between many flights. Istanbul currently creates that connection better than any other major airport.
