Gallery: North America's Top 10 Commercial Aircraft Fleets

Spirit Airlines, operating on a low-cost model, has a fleet of 194 aircraft as of early 2023. The carrier operates an all-Airbus narrowbody aircraft fleet, a mix of older and newer variants of the A320 family. Spirit is looking to modernize its fleet, with plans to phase out older variants of the A320, such as the A319-100. Last month, it took delivery of its first A321neo and, overall, has projections for 33 aircraft deliveries of various A320neo family aircraft this year. In 2022, it opened a two-bay maintenance hangar for specific in-house services in Houston.

Canadian carrier WestJet operates more than 170 aircraft across its main fleet and its subsidiaries, which include a cargo carrier and ultra-low-cost carrier Swoop. Its main fleet numbers more than 100 aircraft and is made up of all Boeing models, with the majority being 737 family variants. It operates seven 787 aircraft, which it mostly uses for transatlantic passenger journeys. The airline outsources much of its heavier maintenance, but last year stated that it was looking to grow its MRO workforce in order to meet returning demand with its fleet returning to full operations in early 2022.

New York City-based carrier JetBlue operates a large fleet of 284 aircraft, mostly comprised of Airbus A220 and A320 family aircraft. It is also a large regional operator of Embraer E190 aircraft, a program for which JetBlue was the launch customer. However, it plans to retire all of these aircraft by 2025 to be replaced by more A220s, following an order for 100 of the aircraft in 2018. JetBlue operates maintenance hangars at New York's JFK Airport and in Orlando, Florida.

Alaska Airlines operates a fleet of approximately 289 aircraft as of February 2023. The vast majority of the fleet is made up of Boeing aircraft, comprised of 737 family variants including newer MAX aircraft. The carrier, based in Anchorage, has 10 A321neos in-service but plans to offload these aircraft by the end of this year when the leases expire. Its Embraer E175s are operated by partners SkyWest Airlines and Horizon Air. Alaska undertakes heavy maintenance services at its main facility in Anchorage, where it services MAX aircraft and has capability for widebodies, in addition to the facility located in Seattle.

Canada's flag carrier operates more than 350 aircraft in total, comprised of the main airline and its subsidiary carriers, which include Air Canada Express and Air Canada Rouge. The main Air Canada fleet is comprised of Airbus and Boeing aircraft. The airline has taken nearly half of its commitment for Airbus A220 aircraft, formerly the Bombardier CSeries program. Deliveries for the narrowbody are expected until 2026 with 15 options also in place. In 2025, it will also start taking deliveries of A321XLR aircraft. The airline's long-term maintenance strategy will consist of a mix of outsourced and in-sourced MRO services, with heavier workscopes such as engine overhauls undertaken by third-party providers.

Regional carrier SkyWest Airlines has a fleet of more than 500 aircraft under contract from U.S. carriers such as the regional divisions of American, Delta, United and Alaska. SkyWest's fleet is made up of Bombardier CRJ and Embraer E190 aircraft.

Southwest Airlines operates the fourth largest commercial fleet in North America as of March 2023, with an all-Boeing 737 family fleet numbering approximately 795 aircraft. The Dallas-based low-cost carrier is embarking on a largescale fleet renewal program and will eventually become the world's largest operator of the 737 MAX. It plans to bring these newer aircraft in to phase out its older 737-700 variants. Despite outsourcing much of its maintenance to third-party MRO providers, the airline does undertake certain tasks in-house and has invested substantially in that side of the operation. In March 2022, it unveiled a new $100 million maintenance operation at Denver Airport.

United Airlines has the third largest airline fleet in North America. The Chicago-based carrier is the world's third biggest commercial operator, with 1,264 aircraft in its fleet as of April 2023. This number is comprised of its main fleet, made up of Boeing and Airbus aircraft, and aircraft operated by its United Express regional service. At the end of 2022, United unveiled plans for a largescale fleet renewal program, which included orders for more 737 MAX and 787 aircraft. The airline now expects to take delivery of about 700 new narrowbody and widebody aircraft by the end of 2032. Its MRO division, United Technical Operations, has two main locations in Chicago and San Francisco.

Delta Air Lines, headquartered in Atlanta, operates approximately 943 aircraft in its mainline fleet with an additional 368 aircraft in its Delta Connection regional airline fleet. Delta operates the second largest commercial fleet in the world. Its MRO division, Delta TechOps, is among the world's biggest maintenance providers by volume. For its main fleet, Delta plans to take delivery of its first Boeing 737 MAX aircraft from 2025, with commitments in place for 100 aircraft. It also plans to drive up its number of Airbus A320neo and A220 aircraft over the next few years.

Dallas-headquartered American Airlines currently operates the world's largest commercial fleet totaling 1,494 aircraft (including American Airlines subsidiaries) as of March 2023 across its main fleet and its subsidiary carriers. The airline, which runs a large in-house maintenance shop in Tulsa, Oklahoma, operates a fleet comprised of Airbus and Boeing narrowbody and widebody aircraft. American Airlines plans to resume deliveries of the 737 MAX 8 this year while it will further ramp up its narrowbody fleet with the start of Airbus A321XLR aircraft from 2024. Its regional subsidiaries and third-party contractors, operating as part of its American Eagle brand, have fleets comprised of Embraer and Bombardier regional jets.