This article lists the deadliest aircraft accidents and incidents involving commercial passenger and cargo flights, military passenger and cargo flights, or general aviation flights that have been involved in a ground or mid-air collision.

As of 15 April 2024, 206 accidents and incidents have resulted in at least 100 fatalities, 34 at least 200 fatalities, eight at least 300 fatalities, and four at least 500 fatalities.

On 17 September 1908, nearly five years after the pioneering flight of the Wright brothers on 17 December 1903,^[1] Thomas Selfridge became the first fatality of powered flight while flying as a passenger with Orville Wright during a demonstration of the Wright Model A at Fort Myer, Virginia.^[2] On 7 September 1909, Eugène Lefebvre was the first to be killed while piloting a powered airplane, while the first fatal mid-air collision occurred on 19 June 1912, near Douai, France, killing the pilot of each aircraft.^[3] Since the deaths of these early aviation pioneers, the scale of fatal aircraft accidents has increased in proportion to the size and capacity of airplanes.

The greatest number of passenger fatalities involving one airline in a single calendar year occurred in 2014 with Malaysia Airlines, when 537 people died (presumably - with the wreckage unrecovered, the death toll is not entirely confirmed) in the disappearance of Flight 370 on 8 March and the shootdown of Flight 17 on 17 July. When including ground fatalities, American Airlines holds this distinction, with the 2001 crashes of Flight 11 and Flight 77 on 11 September, and Flight 587 on 12 November, with a combined total of approximately 2,000 deaths, including 416 people on the three aircraft.^[4] The deliberate crashes of the aforementioned American Airlines Flight 11, as well as United Airlines Flight 175 at the World Trade Center, and the subsequent collapse of both towers on 11 September 2001 caused 2,606 ground fatalities in addition to the deaths of the 157 people on board both flights, making it the deadliest aviation disaster in history.^[5][6]

The most fatalities in any aviation accident in history occurred at the Tenerife North–Ciudad de La Laguna Airport (then Los Rodeos Airport) in Tenerife, Canary Islands, Spain, on 27 March 1977, when a KLM Boeing 747-206B and a Pan Am Boeing 747-121 collided on a runway, killing 583 people.^[7] The largest number of fatalities from the accidental crash of a single aircraft occurred on 12 August 1985, when Japan Airlines Flight 123, a Boeing 747SR-46 en route from Tokyo to Osaka, crashed at Mount Takamagahara in Ueno, Gunma Prefecture, Japan, killing 520 people.^[8] The greatest number of fatalities from a mid-air collision occurred to the west of New Delhi, India, on 12 November 1996, when a Saudi Arabian Airlines Boeing 747-168B en route from Delhi to Dhahran, Saudi Arabia, collided with a Kazakhstan Airlines Ilyushin Il-76TD en route from Shymkent, Kazakhstan, to Delhi, killing all 349 people aboard both aircraft.^[9]

In 2012, Boeing released a study of worldwide commercial jet airplane accidents between 1959 and 2011, reporting 1,798 accidents, 603 categorized as fatal, which accounted for 29,025 onboard fatalities and an additional 1,173 ground or noncommercial aircraft collision deaths.^[10] The Boeing analysis suggests a decrease of commercial aviation accident fatality rates toward the end of the study period.

The US Code of Federal Regulations defines an accident as "an occurrence associated with the operation of an aircraft, which takes place between the time any person boards the aircraft with the intention of flight and all such persons have disembarked, and in which any person suffers death or serious injury, or in which the aircraft receives substantial damage;" an incident as "an occurrence other than an accident, associated with the operation of an aircraft, which affects or could affect the safety of operations;" and a fatal injury as one which results in death within 30 days of the accident.^[11] The definitions of accident, incident, and fatality in the Code of Federal Regulations, and used by the FAA and NTSB, are generally consistent with those found in the ICAO Chicago Convention on International Civil Aviation Annex 13.^[10][12]