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Air travel can take you almost anywhere in the world. And unless you live in one of the biggest cities and travel only to the biggest cities, there’s a good chance you’ll have to make a connection or two from time to time along the way. Recently, air travel data company OAG released their Megahubs Index 2019, analyzing flight information to determine the 50 most internationally connected airports in the world, the 25 most domestically connected airports in the U.S., and the 25 most connected airports for low-cost carriers.

What does it mean to be a connected airport?

When it comes to air travel, connectivity is key. Adventurous travelers want to know how to get to the most places in the simplest way possible. The OAG Megahubs Index looks at practical connections. OAG analyzed the largest 200 airports and largest 200 international airports in the world on the busiest aviation day of the year to find all possible connections within a six-hour time window, factoring in the minimum time required to meet a connection at that airport.

In other words, OAG didn’t include impossible connections including flights that don’t meet an airport’s minimum connecting time criteria, nor did they include connections that leave more than six hours after the first flight lands.

What are the top connected airports?

These top connected airports are the ones you might encounter on your next flights, international, domestic, and low-cost. And while practical, with a connection window of up to six hours, you may want to check out NerdWallet’s guide for getting airport lounge access.


The results declared London Heathrow the most internationally connected airport in the world. British Airways runs 51% of flights at LHR, and on a single day in 2019, LHR will have a potential of 65,294 flight connections within the allotted six-hour window.

A 51% share of the flights in and out of an airport is not the largest percentage in the results. Among the top 25 most internationally connected airports, American Airlines has the highest share of flights at any, with 85% of those at Dallas-Fort Worth, which comes in at 19th most connected international airport.

Top international connected airports

Connectivity index

Dominant carrier

LHR – London Heathrow, UK


British Airways

FRA – Frankfurt, Germany



ORD – Chicago O’Hare, U.S.



AMS – Amsterdam, Netherlands



MUC – Munich, Germany




For travelers looking for low-cost connections, Kuala Lumpur won the award for the most interconnected airport for low-cost carriers. AirAsia has 41% of the flights at that hub. Asian airports take the first four low-cost spots — Malaysia (KUL), Philippines (MNL), Singapore (SIN), and Korea (ICN) — before the U.S.’s San Diego airport snuck in, with Southwest Airlines leading 39% of their flights.

Top low-cost international connected airports

Connectivity index

Dominant carrier

KUL – Kuala Lampur, Malaysia



MNL – Manila, Philippines


Cebu Pacific Air

SIN – Singapore


Singapore Airlines

ICN – Seoul, South Korea


Korean Air

SAN – San Diego, U.S.




Chatting with a group of friends about Chicago O’Hare recently, I was the only one who didn’t rue layovers there. That’s good for me, as ORD came in first in domestic connectivity in the U.S. and third for international connectivity.

Also of note, it’s no surprise that Denver came in fifth for airports with domestic connectivity, as United increased flights out of Denver to 500 from around 360, encouraging Denver denizens to make sure they have their MileagePlus cards on standby.

Top connected domestic airports in the U.S.

Connectivity index

Dominant carrier

ORD – Chicago O’Hare



ATL – Atlanta



DFW – Dallas Fort Worth



CLT – Charlotte



DEN – Denver



OAG reports that there will be 8.2 billion air passengers by 2037, meaning interconnected airports will only increase in importance as people continue to find new ways to find adventure, connect with loved ones all over the world, and travel for business.

This report doesn’t focus on where you’re going, but the places you’ll pass through on your travels. The airports in this report will need to continue to expand services to their ever-growing list of travelers going to an ever-growing list of destinations. But in the meantime, don’t be surprised to connect at LHR on your next international trip.

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