The Official Airline Guide published its OAG Megahubs 2026 ranking on 16 September 2026, placing Delhi’s Indira Gandhi International Airport (IGIA) at 28th among the world’s most connected airports. Istanbul Airport (IST) in Turkiye took first place with flight links to 337 destinations, followed by London Heathrow (LHR) in second place and Amsterdam Schiphol (AMS) in third. Delhi’s jump of 11 places from 39th in 2025 makes it the only Indian airport in the global top 50 and underlines its growing role as South Asia’s leading transfer hub.
What Is OAG and What Is an Airport Megahub?
The Official Airline Guide (OAG) is a global aviation data company that tracks airline schedules and flight connections across the world. An airport megahub is an airport that works very well as a transfer point, where a large number of arriving flights connect smoothly to a large number of departing flights within a short time.
OAG was first published as the Official Aviation Guide of the Airways in February 1929 in the United States. The guide initially listed only 35 airlines operating 300 flights. Over nearly a century, OAG has grown into an aviation intelligence firm headquartered in Luton, United Kingdom, covering more than 900 airlines and over 4,000 airports worldwide.
A megahub is different from the busiest or the largest airport. The busiest airport handles the most passengers or seats. A megahub handles the most useful connections. OAG measures this by comparing two things. The first is the number of possible scheduled connections between incoming and outgoing flights. The second is the number of destinations served from the airport. An airport with a high ratio of connections to destinations ranks higher, because it gives each traveller more onward options per destination.
How Is the OAG Megahubs 2026 Index Calculated?
The OAG Megahubs 2026 index is based on flight data for the 12 months to August 2026. OAG analysed the 100 largest airports in the world and the 100 largest international airports, based on total scheduled seats. From this pool, OAG studied 201 airports in detail.
OAG counted all possible connections on the busiest day for global aviation in the year, which was Sunday, 2 August 2026. A connection was counted only if the waiting time between the arriving flight and the departing flight was within six hours and met the Minimum Connection Time (MCT) for that airport. MCT is the shortest time needed for a passenger and baggage to move from one flight to another at a specific airport. OAG also applied a rule called maximum circuity of 150, which removes very indirect routes that no sensible traveller would choose.
The count includes three types of international transfers. These are domestic to international, international to domestic, and international to international. OAG then divided the total possible connections by the number of destinations to get a connectivity score. The airports with the highest scores form the Top 50 International Megahubs.
OAG publishes two related lists with the same idea but different rules. The Top 25 Low Cost Carrier (LCC) Megahubs list counts only low cost flights. LCC means airlines that offer low fares with fewer free services. The Top 25 United States Domestic Megahubs list counts only domestic connections inside the US, with a shorter connection window of three hours and a base day of 23 July 2026.
OAG Megahubs 2026: Top 10 Most Connected Airports in the World
The OAG Megahubs 2026 report shows a clear shift at the top. Istanbul Airport (IST) moved from second place in 2025 to first place in 2026. London Heathrow (LHR) slipped from first to second. Amsterdam Schiphol (AMS) held third place, while Kuala Lumpur (KUL) held fourth place as the most connected airport in Asia.
The Asia Pacific region dominates the upper ranks, with eight airports in the global top 20. Chinese hubs show a full recovery after the pandemic years. Shanghai Pudong (PVG) rose from 19th to 14th, Guangzhou Baiyun (CAN) rose from 36th to 19th, and Hong Kong (HKG) returned to the top 20 by moving from 22nd to 20th. In the Americas, Chicago O’Hare (ORD) rose from seventh to fifth and became the most connected airport in that region.
| Rank 2026 | Airport | Destinations Served | Dominant Airline |
|---|---|---|---|
| 1 | Istanbul Airport (IST), Turkiye | 337 | Turkish Airlines (80 percent of flights) |
| 2 | London Heathrow (LHR), United Kingdom | 227 | British Airways (51 percent of flights) |
| 3 | Amsterdam Schiphol (AMS), Netherlands | 281 | KLM Royal Dutch Airlines (56 percent of flights) |
| 4 | Kuala Lumpur (KUL), Malaysia | 154 | AirAsia group carriers |
| 5 | Chicago O’Hare (ORD), United States | 308 | United Airlines (49 percent of flights) |
| 6 | Seoul Incheon (ICN), South Korea | 179 | Mixed full service and low cost carriers |
| 7 | Frankfurt (FRA), Germany | 310 | Lufthansa group carriers |
| 8 | Tokyo Haneda (HND), Japan | 107 | Japan Airlines and All Nippon Airways |
| 9 | Paris Charles de Gaulle (CDG), France | 295 | Air France (57 percent of flights) |
| 10 | Atlanta Hartsfield Jackson (ATL), United States | 261 | Delta Air Lines (80 percent of flights) |
Delhi IGIA at 28th sits just ahead of Dubai (DXB) at 31st in the global table, which is notable because Dubai is widely seen as a major transfer hub for India bound traffic. In the low cost segment, Kuala Lumpur leads the world with nearly 15,000 possible low cost connections. Low cost carriers account for 51 percent of all seats in Southeast Asia, compared with a global average of 34 percent.
Istanbul Airport: The Most Connected Airport With 337 Destinations
Istanbul Airport is the main international airport serving Istanbul, the largest city in Turkiye. Turkiye is a transcontinental country that lies partly in southeastern Europe and partly in western Asia. The airport uses the code IST. The code is assigned by the International Air Transport Association to identify the airport on tickets and baggage tags. The city’s second airport, Sabiha Gokcen (SAW), serves mainly low cost and regional traffic and ranks 21st globally in the same index.
Istanbul Airport offers connections to 337 destinations worldwide, the widest reach of any airport in the report. On the busiest day, OAG counted 89,456 possible connections at Istanbul, giving it a connectivity score of 265.4. London Heathrow, by comparison, offered 55,888 connections across 227 destinations, with a score of 246.2. Amsterdam Schiphol offered 68,189 connections across 281 destinations.
Two factors explain Istanbul’s rise. The first is the network of Turkish Airlines, which operates 80 percent of flights at the airport and flies to more countries than any other airline. The second is geography. Istanbul sits between Europe, Asia, Africa and the Middle East, so flights from east and west can meet there with short detours. Heathrow, in contrast, saw potential connections fall by 6 percent from last year. OAG links this fall to disruption in Middle East schedules, with Heathrow’s capacity to that region down by 25 percent in August 2026.
Delhi Indira Gandhi International Airport Ranked 28th Globally
IGIA stands for Indira Gandhi International Airport. It is the main airport serving New Delhi, the national capital of India. The airport uses the code DEL and is located at Palam, about 16 kilometres southwest of central Delhi. IGIA is operated by Delhi International Airport Limited (DIAL), a consortium led by the GMR Group. DIAL manages the airport under a long term lease from the Airports Authority of India.
IGIA is the busiest airport in India by passenger traffic and flight movements. In the Megahubs 2026 assessment of 201 airports, Delhi connects 160 destinations, including 70 international destinations. A network of 70 airlines, including six domestic carriers, operates from the airport. About 15 lakh transfer passengers pass through IGIA every month. Delhi is the only Indian airport in the global top 50 and is ranked as the top megahub in South Asia.
The jump from 39th in 2025 to 28th in 2026 reverses a dip seen in the previous year, when Delhi had slipped from 24th in 2024. The recovery reflects more flights, more destinations, and better use of domestic feeder traffic to fill international flights. Passengers from cities such as Jaipur, Lucknow, Patna, Ranchi, Indore, Bhubaneswar and Guwahati now use Delhi as a gateway to Europe, North America, Southeast Asia, Australia, the Middle East and Central Asia.
Delhi Airport Terminals and Why Delhi’s Rise Matters for India
Delhi Airport has three active passenger terminals. Terminal 1 (T1) handles mainly domestic low cost traffic. Terminal 2 (T2) handles additional domestic flights. Terminal 3 (T3) is the largest building and handles all international flights along with many domestic full service flights. T3 has the wide body aircraft stands, immigration halls, and transfer areas needed for large scale international to domestic connections.
Delhi’s hub model is built on the scale of India’s domestic market. Domestic passengers from smaller cities arrive in Delhi in the morning and connect to afternoon and night flights to London, New York, Singapore, Dubai and Sydney. International passengers arriving in Delhi do the reverse and connect to onward domestic flights. This two way flow raises the number of possible connections without needing to add many new destinations. That is exactly what the megahub score rewards.
Delhi is also adding direct links to new markets. Philippine Airlines is expected to start Delhi to Manila flights by mid November 2026, making Delhi its first destination in India. EVA Air will start Delhi to Taipei flights from 1 December 2026, creating Delhi’s first direct link to Taiwan. Talks are underway with carriers from Russia and Mongolia for future direct services. Airport managers are also examining an airside transfer link between Terminal 1 and Terminal 3, so connecting passengers would not need to exit to the landside road area to change terminals.
For India, a stronger Delhi hub means fewer Indians need to change planes in foreign hubs to reach distant markets. It keeps more ticket revenue, jobs and logistics activity inside the country. It also supports tourism, trade in high value goods, and the growth of airlines that base aircraft and crew in Delhi.
Key Takeaways
- Delhi’s Indira Gandhi International Airport (IGIA) ranked 28th in the OAG Megahubs 2026 report, climbing 11 places from 39th in 2025.
- Istanbul Airport (IST) in Turkiye was ranked the most connected airport in the world with links to 337 destinations.
- London Heathrow (LHR) ranked second and Amsterdam Schiphol (AMS) ranked third in the OAG Megahubs 2026 global list.
- The Official Airline Guide (OAG), founded in 1929 and headquartered in Luton, United Kingdom, based the 2026 ranking on connections counted on 2 August 2026 within a six hour transfer window.
- IGIA connects 160 destinations, including 70 international destinations, and is served by 70 airlines; it is operated by Delhi International Airport Limited (DIAL) and is the only Indian airport in the global top 50.
