It is located in the Sepang District of Selangor, approximately 45 km (28 mi) south of downtown Kuala Lumpur and serves the city's greater conurbation.

It was created as part of the Multimedia Super Corridor, a grand development plan for Malaysia.

[10] Kuala Lumpur International Airport was officially inaugurated by the tenth Yang di-Pertuan Agong, Tuanku Ja'afar of Negeri Sembilan, on 27 June 1998, shortly before the 1998 Commonwealth Games.

The aerobridge and bay allocation systems broke down, with queues building up throughout the airport and the baggage handling breaking down.

[13] Most of these issues were remedied eventually, though the baggage handling system was plagued with problems until it was put up for a complete replacement tender in 2007.

The airport is also largely overshadowed by the more internationally renowned Changi Airport located approximately 300 kilometres (190 mi) to the southeast in Singapore, especially in regards to connecting flights by various airlines or Malaysians especially living in the southern parts of the country (e.g. Johor) preferring to travel via Changi rather than at KLIA.

The first year of opening immediately saw reduction of passenger numbers as some airlines, including All Nippon Airways (resumed on 1 September 2015), British Airways (reinstated on 28 May 2015 until 28 March 2021[14]), Lufthansa (resumed between 28 March 2004[15] until 28 February 2016)[16] discontinued their flights.

Spanning 38.4m along a grid pattern allowing for future expansions, the abstract symbolic architecture by the late Kisho Kurokawa encompasses the Islamic geometry and cutting-edge technology with the tropical rainforest in mind.

The contact pier is an extension of the main terminal building with gates marked with prefix A and B for domestic departures, G and H for international flights.

The 176,000 square metres (1,890,000 sq ft) satellite building accommodates international flights departing and arriving at KLIA T1.

[36] There is a wide array of duty-free shops and prestige brand boutiques in the satellite building.

This includes international brands such as Burberry, Harrods, Montblanc, Salvatore Ferragamo, and Hermes.

Under Malaysia Airports Berhad retail optimisation plan, the retail space in satellite terminal A will be further optimised to increase its revenue derived from commercial space rental and a percentage of sale receipts to 50% by year 2010 which currently stands at 35%.

Some notable improvements that will be seen after the refurbishments will be the Jungle Boardwalk[38] which will be the first of its kind in the world and larger mezzanine floor to accommodate F&B outlets and viewing galleries.

[44] The main terminal building of KLIA T2 is connected with its satellite piers with a skybridge, making it the first airport in Asia with such facility.

[48] Gateway@klia2 is an integrated shopping complex that is connected to the main KLIA T2 terminal building.

[52] The now defunct 36,000 square metres (390,000 sq ft) low cost carrier terminal (LCCT) was opened at Kuala Lumpur International Airport on 23 March 2006 to cater for the growing number of users of low-cost airlines, especially the passengers of Malaysia's "no-frills" airline AirAsia.

[54] MAHB also aims to establish a Hajj and Umrah Terminal with a capacity of five mppa, specifically catering to Muslim pilgrims traveling to Saudi Arabia.

This terminal would enable Saudi Arabia's immigration pre-clearance procedures to be conducted at KLIA, reducing waiting times at King Abdulaziz International Airport in Jeddah.

[56][57] AirAsia planned to move its head office to a new 613,383 square feet (56,985.1 m2), RM140mil facility constructed at klia2.

[58] Aireen Omar, the AirAsia Country CEO of Malaysia, stated that the headquarters needed to be redesigned because in the klia2 plans the location of the control tower had been changed.

[60] Filipina AirAsia X flight attendant January Ann Baysa gave the building the name "RedQuarters" or "RedQ", and its groundbreaking ceremony was held in November 2014.

[210] No airside connection currently exists between the Main Terminal Building and Terminal 2; connecting passengers must clear Malaysian immigration and customs checks before taking a landside transportation option (Express Rail Link, bus or taxi).

Kuala Lumpur International Airport has bus terminals in both KLIA and KLIA2 building which serves local buses, city express and intercity express buses to various destination in Kuala Lumpur, Klang Valley and also various parts of Peninsular Malaysia, as well as shuttles between KLIA and KLIA2, terminals to Long Term Car Park and terminals to Mitsui Outlet Park.

There is sufficient land and capacity to develop facilities to handle up to 97.5 million passengers a year, four runways by 2020 and two mega-terminals, each linked with satellite terminals.

[10] On 12 December 2024, Transport Minister, Anthony Loke Siew Fook announced that plans to expand KLIA are in the pipeline to cater for the increasing flight passengers.

Works include the provision of shoulders on both sides of the two existing runways of 15 meters as well as the taxiways, building additional aerobridges at the three departure halls, namely C17, C27 and C37, and enhancing the mezzanine lounges for upper deck passengers of the aircraft at the departure halls.

Emirates is the only current operator of the Airbus A380 to Kuala Lumpur; its services commenced on 1 January 2012.

[212] Malaysia Airlines started its A380 services from Kuala Lumpur to London on 1 July 2012 before retiring the aircraft type at the end of 2018.

[213] On 22 November 2024, KLIA was awarded Large Airport of the Year 2024 by Centre for Aviation (CAPA) for its exceptional connectivity performance in view of the strong regional competition, commitment to the development of major infrastructure and flexibility in servicing both full-fledged and low-cost airlines.