The Aircraft Replacing The Iconic Boeing 737-800

Published Oct 12, 2026, 7:00 PM EDT Brandon's passion for aviation started at a young age. He became involved in the flight simulator and VATSIM communities, which sparked his interest in aviation and eventually led him to earn his private pilot license. Outside of work, he continues to build flight hours, explore new airports, and stay involved in the aviation community. Boeing built 4,991 737-800s, making it the most-produced variant of the most-produced commercial jet in history. Its replacement is the MAX 8, which Boeing positions as the versatile model of the 737 MAX family and markets as delivering roughly 20% lower fuel use and CO2 emissions than the aircraft it replaces. Capacity is what makes it a direct successor. The MAX 8 seats roughly 162 to 189 passengers, depending on configuration, the same range airlines configured the 737-800 across, allowing a carrier to swap airframes without redesigning its network. The transition is not uniform. Japan Airlines (JAL) holds 38 MAX 8s on order explicitly to replace 62 737-800s, and Malaysia Airlines is targeting full replacement of its 38 737-800s by 2030. KLM went the other way, ordering 100 Airbus A320neo family aircraft to replace its short-haul Boeing fleet. United Airlines has concentrated its outstanding narrowbody orders on the MAX 9 and MAX 10 rather than the MAX 8. Boeing and Turkish Airlines finalized an order last month for up to 150 MAX aircraft, comprising 100 firm MAX 8s and options for 50 more. The MAX 8 Is The Direct Replacement Boeing delivered 4,991 commercial 737-800s, making it the most-ordered variant of the most-produced commercial jet in history. Assembly of passenger 737NGs ended in 2019, with the last airframe going to KLM Royal Dutch Airlines in December 2019 and the final two deliveries to China Eastern Airlines on January 5, 2020. Its replacement is the MAX 8, as American Airlines' aircraft appraisal filing plainly describes. "The 737 MAX 8, also referred to as the 737-8, was the first member of the MAX generation to be delivered, serving as the successor to the highly popular 737-800," it explains. The FAA certified the MAX 8 in March 2017 and delivered the first to Malaysian carrier Malindo Air on May 16, 2017. It has since become the most widely ordered variant in the family. As of January 2026, customers had ordered over 4,785 MAX 8s, including 230 MAX 8-200s, and had delivered over 1,800 commercial MAX 8s. By comparison, its closest competitor, the Airbus A320neo, had taken 4,107 commercial orders with 2,323 delivered as of December 31, 2025. The MAX 8 is a direct successor rather than an approximate one because it occupies the same capacity point. The larger MAX 9 and MAX 10 add seats, which makes them growth aircraft for carriers that want more capacity per departure. The MAX 10 has also not received FAA certification, and the agency has not provided a timeline for approval, leaving airlines planning around it with an open question the MAX 8 does not carry. The MAX 8 is the variant an airline can order and configure as a like-for-like substitute for a 737-800 without changing what it sells on the route. What Boeing Claims On Efficiency Credit: Felix Tchvertkin | Shutterstock Boeing markets the MAX family as delivering roughly 20% lower fuel use and carbon emissions than the airplanes it replaces. That figure covers the family against the older aircraft it generally displaces across the market. Measured specifically against the 737-800, the gain is smaller. American Airlines' appraisal filing puts the MAX 8 at "14% better fuel economy than its predecessor, the 737-800." Simple Flying previously reported 15% when covering JAL's order. The engine accounts for most of it. The MAX 8 uses the CFM LEAP-1B, a high-bypass turbofan built by CFM International, the joint venture between GE Aerospace and Safran Aircraft Engines, replacing the CFM56-7B that powered the 737NG. Boeing paired it with aerodynamic improvements to the aft body and a redesigned winglet. The cabin uses Boeing's Sky Interior lighting along with lighter seats and lavatories, which contribute marginally to weight. Range improved alongside fuel burn. The MAX 8 covers 3,300 to 3,859 nautical miles (6,112 to 7,147 km), depending on configuration, versus 3,115 nautical miles (5,769 km) for the 737-800. That gives an operator roughly 200 to 700 additional nautical miles (370 to 1,296 km) on the same airframe footprint, which opens routes the 737-800 could not reach without payload restrictions. For most carriers, fuel savings drive the business case, and range is a secondary benefit, but for airlines flying near the 737-800's limit, it changes which markets the aircraft can serve. The Airlines Actually Swapping 800s For MAX 8s Credit: Markus Mainka | Shutterstock JAL is the clearest documented case. The carrier ordered 21 MAX 8s in March 2023 and added 17 more on March 19, 2025, bringing the total to 38. JAL stated the aircraft "will replace the single-aisle Boeing 737-800 aircraft currently serving mainly on domestic routes." First deliveries begin in the fiscal year starting April 2026. The order sits inside a broader renewal. JAL is ordering 11 A321neos to replace 767s on Haneda routes, plus three A350-900s for domestic service and five A350-1000s for international service. The group has described the program as introducing approximately 90 new aircraft. JAL framed the rationale in operating terms, saying that renewing the fleet in line with supply and demand would further enhance profitability. Southwest Airlines is the largest MAX 8 operator and is running the same transition at far greater scale. The carrier ended 2025 with 803 737s, including 300 MAX 8s, and retired 55 aircraft during the year, including seven 737-800s, while taking delivery of 55 MAX 8s. As of January 29, 2026, its order book held 467 firm MAX aircraft, comprising 271 MAX 7s and 196 MAX 8s, plus 150 options. Southwest expects 66 MAX 8 deliveries in 2026, while planning to retire roughly 60 aircraft, close to a one-for-one exchange across a fleet of more than 800. Why The Transition Is Not One-For-One Credit: Markus Mainka | Shutterstock Not every 737-800 operator is replacing the type with a MAX 8, and some are leaving Boeing entirely. KLM signed a memorandum of understanding with Airbus for a firm order of 100 A320neo and A321neo aircraft plus 60 options, covering both the mainline short-haul fleet and low-cost subsidiary Transavia, with the aircraft replacing the Boeing 737-800NGs then in service. KLM CEO Pieter Elbers framed the decision around emissions, noise, and efficiency rather than capacity. Qantas made the same call with a different Airbus type. The carrier selected the A321XLR to replace its 737-800s and exercised 20 further purchase rights in August 2025, bringing its total A321XLR order to 48. The XLR is substantially larger than a 737-800 with 200 seats in domestic configuration, meaning Qantas is adding capacity per departure rather than matching it. United has moved in the same direction while staying with Boeing. American's appraisal filing notes that United became one of the largest MAX 10 customers by converting 100 MAX 9 orders to the MAX 10. That is a deliberate shift up the family rather than a like-for-like swap, and it carries risk the MAX 8 does not, since the MAX 10 remains uncertified with no FAA timeline. Boeing's production constraints compound the problem for everyone. The FAA capped MAX output at 38 aircraft per month following the January 2024 door plug incident, and Southwest's own filing acknowledges that its delivery and retirement expectations remain fluid and subject to Boeing's production capability. Turkish Airlines And The Scale Of The Order Book Credit: Renatas Repcinskas | Shutterstock Boeing and Turkish Airlines finalized an order for up to 150 MAX aircraft on September 23, in New York, with Turkish President Recep Tayyip Erdoğan present. The deal covers 100 firm MAX 8s and options for 50 more MAX aircraft, concluding discussions that began in 2025 as part of a proposed order for up to 225 Boeing aircraft. It is Turkish Airlines' largest Boeing single-aisle order, and it follows the carrier's 2025 order for up to 75 787 Dreamliners. The agreement includes substitution rights for the MAX 10, the largest variant in the family, allowing Turkish Airlines to shift part of the order to a larger aircraft as its network requires. That flexibility is increasingly standard in MAX orders and reflects the uncertainty around the MAX 10's certification timeline. Turkish Airlines and its low-cost subsidiary AJet together operate more than 200 Boeing aircraft, including the 737 MAX, the 787 Dreamliner, the 777, the 737 Next Generation, and the 777 Freighter, making the carrier one of the world's largest mixed-generation 737 operators. The order took more than a year to close. Turkish Airlines chairman Prof Murat Şeker and Boeing both framed the purchase around the airline's expansion from Istanbul rather than around fleet replacement specifically, though the carrier's existing 737NG fleet gives it ample scope for both. For an airline operating 116 737s across the 800, 900, MAX 8, and MAX 9 variants, an order of this size renews and grows the fleet at once.