Comparing and measuring airlines can be done in numerous ways: from such objective numbers like profitability, destination count, complex indicators like Available Seat Kilometers (ASK) or Revenue Passenger Kilometers (RPK) to subjective or purchased measurements like passenger experience or star ratings. However, one figure can definitely tell the size of an airline – the size of the fleet. Without aircraft, an airline is not really an airline, no matter how hard the company tries to tell the world otherwise (looking at you, Baltia Air Lines!).

Nevertheless, as the year ends, a question on everybody’s mind remains – who were the biggest carriers in 2019, as the year ended?

5. China Southern Airlines – 626 aircraft

China Southern Airlines (ZNH) is currently the largest airline in Asia and one of the biggest carriers in the world in terms of fleet size. The state-owned airline, founded in 1988, operates a wide variety of aircraft: from its smallest planes, like the Airbus A319 or the Boeing 737-700 to being in one of the most exclusive airline clubs, the Airbus A380 operator club. China Southern Airlines (ZNH) , as of December 1, 2019, flies 626 jets, according to planespotters.net data. Operating 3,000 daily flights to 224 destinations and 40 different countries, the Chinese carrier has established itself as one of the biggest airlines in the world.

While most of its destinations are located in Asia, China Southern Airlines (ZNH) ‘ aircraft can be seen in such cities as Chicago, New York, Los Angeles, London, Paris, Rome, San Francisco and many other global metropolises.

4. Southwest Airlines – 748 aircraft

The exclusively Boeing 737 operator, using the plane type ever since the company’s first flight in 1971, apart from a brief stint with the Boeing 727 in the 1980s, ends the year with 748 jets. Sadly, the carrier was one of the most affected airlines by the Boeing 737 MAX crisis, as Southwest Airlines (LUV) has 280 firm MAX jets on order. In the airline’s latest financial results report, the Dallas Love Field (DAL) based carrier has noted that it expected 41 new deliveries of the MAX in 2019. Now, Southwest expects seven aircraft deliveries to come in Q4 2019, while the rest would be pushed back into 2020.

Currently, it has 34 737 MAX aircraft stored due to the groundings.

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3. United Airlines – 789 aircraft

Tracing its history back to 1926, the full-service carrier is one of the lucky few to survive the aftermath of two major events in the United States aviation industry – the 1978 deregulation act and the aftermath of September 11 attacks, despite it declaring bankruptcy on December 9, 2002. Nevertheless, United survived the headwinds and managed to grow to be one of the biggest airlines in the world after the merger with Continental Airlines in 2010.

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One of The Big Three US airlines, United, ended the year with 789 aircraft, average age of 15.7 years. The Chicago based airline recently increased its order backlog with a deal for 50 Airbus A321XLR aircraft announced on December 4, 2019.

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United Airlines has finally decided on which aircraft will replace its aging Boeing 757-200 fleet. The spot is going to be occupied by a brand new extra long-range narrow-body, the Airbus A321XLR. The first of new airliners are expected to serve United’s international routes already in 2024, the U.S. legacy carrier announced on December 3, 2019. 
 

2. Delta Air Lines – 910 aircraft

Operating out the biggest airport in the world in terms of passenger traffic, Atlanta Hartsfield International Airport (ATL), Delta Air Lines boasts the second-largest fleet in the world. The case of Delta Air Lines fleet is quite a curious one – all of the aforementioned airlines on the list are 737 MAX operators, being heavily affected by the ongoing aircraft groundings. However, Delta was never persuaded by Boeing – while the Chief Executive Officer of the airline, Ed Bastian noted that it was a close call of signing a deal during an earnings call in July 2019, it never materialized into a firm order or a Letter of Intention/Memorandum of Understanding (LoI/MoU). At the same earnings call, Bastian mentioned that Q2 2019 was a record quarter for Delta, in part due to the fact that it does not operate the 737 MAX. The airline also remains one of the remaining active operators of the MD-80, as other operators already phased out their Mad Dogs.

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On June 27, 2019, Boeing delivered the last jet in Delta’s Boeing backlog, a 737-900ER. From that point on, the Atlanta based carrier has only Airbus jets on order, including the Airbus A220.

As of December 1, 2019, Delta Air Lines has 910 aircraft, planespotters.net data shows.

1. American Airlines – 941 aircraft

For quite some time now, American Airlines (A1G) (AAL) is the largest operator in the world in terms of the amount the carrier possesses. The Dallas/Fort Worth hub has become one of the most important connections in the United States and the world due to AA’s size. Starting its history in 1926, the airline has achieved its massive size due to multiple mergers, including with Trans World Airlines in 2001 and US Airways in 2013, with the US Airways brand flying its last flight in 2015. At the time of the merger, US Airways had 344 aircraft and the companies formed the largest airline in the world.

American Airlines (A1G) (AAL) is also the airline that prompted Boeing to re-engine the 737 and announce the 737 MAX in 2011, when the carrier announced a then record-breaking deal for 400 narrow-body aircraft, including 100 “of Boeing's expected new evolution of the 737NG, with a new engine that would offer even more significant fuel-efficiency gains over today's models.”

The airline ends the year with 941 aircraft, including 24 grounded 737 MAX aircraft.

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American Airlines and Southwest Airlines have once again postponed the return date for the Boeing 737 MAX. They now expect to see the aircraft take back to the skies in early March 2020.
 

Thus, this concludes the list of the biggest airlines in 2019. To sum, the biggest airlines in 2019 were:

5.     China Southern Airlines (ZNH) – 626 aircraft

4.     Southwest Airlines (LUV) – 748 aircraft

3.     United Airlines – 789 aircraft

2.     Delta Air Lines – 910 aircraft

1.     American Airlines (A1G) (AAL) – 941 aircraft