Heathrow loses crown as world’s most connected airport
London Heathrow has lost its position as the world’s most internationally connected airport, falling to second place behind Istanbul Airport in OAG’s 2026 Megahubs ranking.
For UK-based business travellers, Heathrow remains one of the world’s most important international gateways, but the new ranking highlights how the choice of connecting hub is changing, particularly for business travel to destinations in Asia, Africa and the Middle East.
OAG’s annual Megahubs Index measures the connectivity of the world’s major international airports by looking at the number of possible connections between inbound and outbound flights within a six-hour window, together with the number of destinations served. The 2026 ranking is based on the busiest day for global aviation in the year to August, Sunday 2 August 2026.
Heathrow, which occupied first place in 2025, has fallen to second after its potential connections on the busiest day declined by 6% year on year. OAG says Heathrow’s connectivity has also been affected by continuing disruption to Middle East schedules, with capacity between Heathrow and the region down 25% in August compared with the previous year.
Despite losing the top position, Heathrow remains extraordinarily well connected. OAG recorded 55,888 potential connections and 227 destinations for Heathrow, with British Airways accounting for 51% of capacity at the airport.
Istanbul overtakes Heathrow
Istanbul Airport has moved from second place in 2025 to become the world’s most connected international airport for the first time.
OAG recorded 89,456 potential connections at Istanbul and a network covering 337 destinations. Turkish Airlines is responsible for 80% of capacity at the airport, demonstrating the importance of a strong home carrier in creating an effective connecting hub.
OAG Chief Analyst John Grant said:
“The 2026 rankings reflect a global aviation landscape that is still recalibrating after significant disruption. Istanbul's rise to the top reflects the strength of Turkish Airlines' network and the airport's geographic position as a connecting hub between east and west. The recovery of Chinese airports is equally significant. The data suggests the post-pandemic adjustment in that market is now complete.”
Amsterdam Schiphol retains third position in the global ranking, while Kuala Lumpur remains fourth and is the highest-ranked Asian airport. Chicago O’Hare has climbed from seventh to fifth and is now the most connected airport in the Americas.
What does this mean for business travel?
For UK business travellers, Heathrow slipping to second place should be kept in perspective. It does not mean Heathrow suddenly offers poor connectivity, nor does the ranking suggest that Istanbul is necessarily a better choice for every journey.
What it does demonstrate is the growing range of options available when planning international business travel.
Istanbul’s geographical position between Europe and Asia, combined with Turkish Airlines’ extensive network, makes it an increasingly significant connecting point for journeys from the UK to destinations further east and south.
Paul Baker, Sales Director at Global Travel Management, said:
“Heathrow remains an incredibly important airport for UK business travellers, so falling from first to second in a global ranking doesn’t suddenly change that. What is interesting is the continued growth of Istanbul as a connecting hub. For some journeys, particularly where there isn’t a convenient direct flight from the UK, having another well-connected option can give travellers more choice over schedules, fares and how they reach their final destination.”
The rankings also illustrate a longer-term challenge facing Heathrow. OAG has highlighted the airport’s limited capacity compared with Istanbul, which has greater scope for expansion. In subsequent analysis of its Megahubs findings, OAG said Heathrow is operating very close to maximum capacity, while Istanbul’s infrastructure allows simultaneous operations across three runways.
For companies managing international business travel, however, airport connectivity is only one part of choosing an itinerary. Journey time, fare, reliability, connection time, traveller wellbeing and the consequences of disruption all need to be considered alongside the number of destinations available through a particular hub.
The latest OAG ranking nevertheless provides a useful reminder that the global aviation map continues to change. Heathrow remains one of the most connected airports on the planet, but Istanbul’s rise demonstrates that UK business travellers have an increasingly powerful alternative when their journey requires a connection.
If you would like further information about flight options through Heathrow, Istanbul or other international hubs for your business travel, please contact your Global Travel Management Account Manager.