Istanbul Airport has risen to second place in the OAG Megahubs 2025 Index, underscoring its growing role as one of the most connected airports in the world.
The annual report from aviation data provider OAG, released in September, ranks global airports by their ability to connect international passengers through single hubs within a six-hour window. London Heathrow retained the top position for the ninth time in the last decade, reflecting its continued dominance as a global connector.
The index measures connectivity by analyzing the ratio of possible international connections to the number of destinations served, providing a benchmark for hub efficiency. In 2025, OAG examined thousands of schedules worldwide, ranking the top 50 airports globally and by region. The results highlight both established leaders in Europe and North America and the rapid ascent of hubs in the Middle East and Asia.
Global Rankings Highlight Europe’s Strength
London Heathrow leads the 2025 Megahubs Index, maintaining its position as the world’s most connected international airport. Istanbul Airport climbed significantly, moving into second place, while Amsterdam Schiphol ranked third. Frankfurt Airport and Paris Charles de Gaulle completed the European-dominated top five, confirming the region’s continued importance in international connectivity.
OAG noted that Istanbul’s rise reflects both the geographic advantage of Turkey’s location and the strategic expansion of Turkish Airlines. The airport has rapidly scaled operations since opening in 2019, becoming one of the busiest international gateways. Amsterdam and Frankfurt also benefited from strong European demand, extensive route networks, and the ability to offer a high volume of onward connections.
“Airports like Istanbul demonstrate how strategic investments and airline partnerships can transform connectivity within just a few years,” said John Grant, Chief Analyst at OAG. “The Megahubs Index shows not only the busiest airports, but those that maximize opportunities for passengers to connect efficiently across continents.”
North America and Asia-Pacific Trends
Chicago O’Hare was ranked as the most connected airport in North America, taking eighth place globally. Atlanta Hartsfield-Jackson and Dallas/Fort Worth also appeared in the global top 20, reflecting the importance of U.S. hubs in domestic and international connectivity. Miami International ranked highest for Latin America, while Toronto Pearson led in Canada.
In Asia-Pacific, Singapore Changi continued to perform strongly, ranking within the top 10 globally. Hong Kong International Airport, Seoul Incheon, and Bangkok Suvarnabhumi also featured prominently, showcasing the recovery of Asia’s international aviation market after several years of pandemic disruption. Beijing Capital and Shanghai Pudong were ranked outside the top 20 but are expected to regain ground as China’s outbound travel accelerates.
Low-Cost Carrier Megahubs
The 2025 index also highlighted the role of low-cost carrier (LCC) airports. Kuala Lumpur International Airport emerged as the top LCC Megahub, with AirAsia accounting for more than half of its international connectivity. Other leading LCC hubs included Delhi Indira Gandhi International and Bangkok Don Mueang, underscoring the strength of budget carriers in Asia’s aviation landscape.
OAG reported that in Europe, Barcelona and London Gatwick ranked highest among LCC hubs, largely driven by easyJet and Vueling’s expansive networks. In North America, Las Vegas and Orlando stood out, supported by carriers such as Southwest and Spirit Airlines. The findings reflect how low-cost airlines are reshaping connectivity in both leisure and business travel markets.
Connectivity as a Competitive Advantage
The Megahubs Index is regarded as a key measure of how airports function as global transit points. While passenger volumes remain important, the index emphasizes efficiency in providing multiple connection options. Airports that rank highly can attract both airlines and passengers seeking convenient transfers, reinforcing their strategic importance in global aviation.
OAG’s 2025 analysis highlighted that connectivity has rebounded to pre-pandemic levels in many regions, though growth is uneven. European and Middle Eastern airports showed the strongest gains, while North America remained stable. Asia-Pacific airports are still in recovery mode but are advancing quickly as international capacity returns.
“Megahubs play a vital role in enabling trade, tourism, and business travel,” said John Grant. “The 2025 results illustrate how airports are adapting to new demand patterns and how connectivity remains central to global economic growth.”
The report concludes that while traditional hubs like London, Frankfurt, and Paris remain dominant, the rise of Istanbul and the resilience of Asian and Middle Eastern airports mark a shift in the balance of global aviation. As airlines adjust their route strategies and governments invest in airport infrastructure, the competition to serve as a top global connector is set to intensify in the coming years.
