With Boeing's 737 MAX still grounded following two fatal crashes, we thought we would take a look and see who the biggest Boeing 737 MAX customers are.

Despite months of effort, aviation regulators are still unable to say when the aircraft will be allowed to fly again. Now into its fifth month of being grounded, airlines are starting to feel the pain. Summer in the Northern Hemisphere is the busiest travel season and the airlines are having to cancel thousands of flights.

Boeings biggest 737 MAX customer, Southwest Airlines, which has 34 737 MAX in its fleet, has joined United and American taking the 737 MAX off its schedule until early November.

Ryanair is still calling the 737 MAX a "Game-Changer"

European low-cost carrier Ryanair announced that, due to all the uncertainty surrounding the 737 MAX, it would now have to put expansion plans on hold. They noted that some airport hubs might have to close.

Ryanair 737-800s
Ryanair has ordered 135 Boeing 737 MAX jetliners. Photo: Ryanair

Ryanair chief executive, Michael O’Leary, said to The Guardian newspaper that he remained committed to the 737 MAX: “We’ve described them as game-changers – and they remain game-changers.”

Ryanair is one of Boeings biggest 737 MAX customers with 135 aircraft on order. While O’Leary remains committed to the MAX he also said: “We’re still operating in the realms of considerable uncertainty ... there are no guarantees.”

Ryanair does not currently operate the Boeing 737 MAX, but was hoping to take delivery of the first five of 135 aircraft this year and then another 58 before next summer.

Which airlines have the most Boeing 737 MAX aircraft?

In the United States, Southwest Airlines, American Airlines and United Airlines all operate flights using the 737 MAX. American and Southwest both fly the 737 MAX 8 while United uses the larger 737 MAX 9.

Norwegain 737 MAX
Norwegian uses the 737 MAX on long-haul flights to North America and the Middle East. Photo: Norwegian

In Europe, Norwegian Air Shuttle is the biggest operator of the Boeing 737 MAX, using the jet on long-haul flights to North America and the Middle East. Below is a list of airlines that were flying the Boeing 737 MAX before the grounding came into effect. The list is in reverse order starting with the 12th biggest operator.

Turkish Airlines

The Istanbul based national flag carrier of Turkey has 12 Boeing 737 MAX aircraft in their fleet. The airline also has orders with Boeing for 40 737 MAX 8s and 10 737 MAX 9s

WestJet Airlines

Canada’s Calgary based WestJet Airlines operates 13 Boeing 737 MAX aircraft and has 21 on order.

Spicejet

Indian low-cost carrier Spicejet operates 13 Boeing 737 MAX aircraft and has 193 on order.

Flydubai

Dubai based low-cost airline Flydubai operates 14 Boeing 737 MAX aircraft and has 236 on order.

United Airlines

Chicago based United Airlines operates 14 Boeing 737 MAX aircraft and has 100 on order.

TUI

Anglo-German leisure travel airline TUI operates 15 Boeing 737 MAX aircraft and has 60 on order.

Air China

Beijing based Air China operates 16 Boeing 737 MAX aircraft and has 29 on order.

Norwegian Air Shuttle

European low-cost carrier Norwegian Air Shuttle operates 18 Boeing 737 MAX aircraft and has 92 on order.

China Southern Airlines

Guangzhou based China Southern Airlines operates 24 Boeing 737 MAX aircraft and has 56 on order.

American Airlines

Dallas based American Airlines operates 24 Boeing 737 MAX aircraft and has 100 on order plus 60 options.

Air Canada

Canadian national flag carrier Air Canada operates 24 Boeing 737 MAX aircraft and has 37 on order.

Southwest Airlines

American budget airline Southwest Airlines operates the world’s biggest fleet of Boeing 737 MAX aircraft with 34 planes. The all-Boeing airline has an order in place for a further 276 of the model.

Here is a  list of all airlines that fly the Boeing 737 MAX and their orders for the aircraft.

list of ailines that fly 737 MAX
List of airlines that fly the 737 MAX and future orders. Image: Wikipedia

Conclusion

Since the 737 MAX grounding Garuda Indonesia has canceled its order with Boeing for the MAX as has Saudi Arabia Airlines. Others meanwhile remain committed, expecting the jetliner to be given the all-clear by the FAA.

I, however, remain skeptical that the public can be convinced to fly the 737 MAX and have a suspicion that Boeing will come out with some sort of re-branding.

What are your opinions on the 737 MAX and when do you think it will fly again?