What Is MTOW? Maximum Takeoff Weight Explained Simply (With Examples)

If you read about aircraft, you will often see the letters MTOW: “the A380 has an MTOW of 575 tonnes”, or “Boeing raised the 787-9’s MTOW to add range”. MTOW stands for maximum takeoff weight, and it is one of the most important numbers about any aircraft. It decides how much fuel, passengers and cargo the aircraft can carry, how far it can fly, and even how much the airline pays in airport fees.

In one line: MTOW is the heaviest weight at which an aircraft is allowed to start its take-off run. It is fixed during certification and never changes, but on any given day the actual allowed take-off weight can be lower because of heat, altitude, runway length and other factors.

In this guide we explain MTOW and the other aircraft weights step by step, with real examples. If you are new to aviation terms, our guides to widebody and narrowbody aircraft are a good place to start.

What Does MTOW Mean?

According to Wikipedia, the maximum takeoff weight (MTOW), also called maximum gross takeoff weight (MGTOW) or maximum takeoff mass (MTOM), is “the maximum weight at which the pilot is allowed to attempt to take off, due to structural or other limits”. It is the heaviest weight at which the aircraft has been shown to meet all the airworthiness requirements that apply to it.

Three things are important to understand:

• It is measured at the start of the take-off run, when the pilots release the brakes.
• It is fixed: the MTOW does not change with altitude, air temperature or runway length.
• It is usually set by the structure: the aircraft must be strong enough to handle all the loads it may face during take-off and flight at that weight.

MTOW is normally given in kilograms or tonnes, or in pounds for American aircraft. For example, Boeing lists the 737 MAX 8 at 82,640 kg (182,200 lb).

MTOW of Popular Airliners

Sources: Airbus and Boeing specifications, as compiled in our A320neo, 737 MAX 8, 787-9, 777-300ER and other reviews; Wikipedia: Airbus A380.

The jump from single-aisle to widebody is huge: an A350-900 can weigh more than three A320neos at take-off. At the top, the A380 weighs 575 tonnes, the most of any airliner; see our list of the largest passenger aircraft.

The Weights That Make Up Take-Off Weight

An aircraft’s weight on any flight is built up in layers. Wikipedia gives a simple formula:

Take-off weight = Operating empty weight + Payload + Fuel on board

Sources: Wikipedia: Operating empty weight; Wikipedia: Zero-fuel weight; Wikipedia: Maximum landing weight.

This explains the airline’s everyday trade-off. With the MTOW fixed, every extra tonne of passengers or cargo means one tonne less fuel, and less fuel means less range. On a long flight, an aircraft may reach its MTOW before its seats or cargo hold are full, so the airline has to leave some payload behind. That is why aircraft makers keep raising MTOWs, as we show below.

MTOW vs Regulated Take-Off Weight

The MTOW is a fixed limit, but on many days the aircraft is not allowed to take off at it. The actual limit for a particular take-off is called the maximum permissible take-off weight, the maximum allowed take-off weight or the regulated take-off weight. It changes from one take-off to the next, and it can never be higher than the MTOW.

Wikipedia lists the factors that can lower it:

• Flap setting: the wing configuration chosen for take-off.
• Airport altitude: thinner air at high airports reduces engine thrust.
• Air temperature: hot air is less dense, which also reduces thrust and lift.
• Runway length: a short runway gives less distance to reach take-off speed.
• Wind: a strong headwind helps; a tailwind is the worst case.
• Runway condition: a dry, paved runway is best; snow or an unpaved surface slows the aircraft.
• Obstacles: the aircraft must climb high enough to clear terrain and buildings beyond the runway.

Pilots and dispatchers calculate a series of limits, such as the field-limited, runway-limited, obstacle-limited and climb-limited weights, and the lowest one becomes the regulated take-off weight for that flight. This is why a fully loaded long-haul flight may need to carry less on a very hot summer afternoon than on a cool night.

Hot weather can even change an airline’s choice of aircraft. Wikipedia reports that Emirates considered cancelling its Boeing 787-10 order in 2019 because the engine margins were not enough for Dubai’s summer heat, and ordered 787-9s instead. See our 787-10 vs A350-900 comparison.

MTOW vs Maximum Landing Weight

An aircraft can usually take off heavier than it can land. The maximum landing weight (MLW) is the heaviest weight at which it may land, and it is almost always lower than the MTOW, because the aircraft burns fuel during the flight. According to Wikipedia, if an aircraft lands too heavy it may suffer structural damage or even break apart.

This matters when a flight has to return soon after take-off, still heavy with fuel. Some aircraft can dump fuel to get down to their MLW; others cannot. Wikipedia describes Air Canada Flight 837, a Boeing 767-300, which suffered a tyre failure and engine fire on take-off from Madrid on 3 February 2020. Because the 767-300 cannot dump fuel, it flew in a holding pattern on one engine for over four hours to burn fuel before landing safely. In a real emergency, pilots may make an overweight landing, after which the aircraft needs a structural inspection.

Why Airlines Want Higher MTOWs

Because a higher MTOW means the aircraft can carry more fuel, more payload, or both. Aircraft makers often strengthen an aircraft over its life to raise its MTOW:

Sources: Wikipedia: Boeing 787; our A330-900neo, A350-900 and A350-1000 reviews.

Sometimes a higher MTOW needs new materials. Wikipedia notes that the Airbus A330’s 242-tonne version and the A330neo use a scandium-aluminium alloy so the structure can take the extra weight without adding much empty weight. For the extreme case of adding fuel, see how the A321XLR reached 101.5 tonnes with a permanent extra fuel tank.

Why an Airline Might Choose a Lower MTOW

It sounds strange, but airlines sometimes certify their aircraft with a lower MTOW than the structure allows. The reason is money: Wikipedia explains that some costs, such as insurance premiums, landing fees and air traffic control fees, are based on MTOW. An airline flying short routes does not need the full weight, so a lower certified MTOW saves fees. Some operators can even vary a “maximum declared take-off weight” for each aircraft under a scheme.

Boeing’s new higher 787 weights are an example: Wikipedia notes that all 787-9s and 787-10s built since December 2025 can use the higher MTOW, but airlines may choose a lower certified weight because the operating weights can affect airport fees.

MTOW and Wake Turbulence Categories

MTOW also decides how far apart aircraft must be when they take off and land. Heavier aircraft leave stronger wake vortices, swirling air behind the wings that can upset a following aircraft; our turbulence guide explains more. ICAO sets four wake turbulence categories by maximum certified take-off mass:

Source: Wikipedia: Wake turbulence category.

That is why you may hear pilots of big jets add “heavy” or “super” to their call sign on the radio, so air traffic control and other pilots leave extra space. ICAO’s distance minimum behind a Super aircraft is 13 km for a following Medium aircraft, against 9.3 km behind a Heavy.

Key Takeaways

• MTOW is the maximum weight at which an aircraft may start its take-off run; it is fixed at certification.
• The regulated take-off weight for a given flight can be lower, because of heat, altitude, runway, wind and obstacles.
• Take-off weight = empty weight + payload + fuel, so more payload means less fuel and less range.
• Maximum landing weight is usually lower than MTOW, which is why heavy aircraft may dump or burn fuel before an early landing.
• MTOW also sets landing fees and wake turbulence categories; the A380 is the only Super.

Frequently Asked Questions

Featured image: FlyingFuel graphic using a photo of EVA Air Cargo Boeing 777F B-16788 on its take-off run at Taipei Taoyuan by 4300streetcar, CC BY 4.0, via Wikimedia Commons.