British Airways plc or BA (lseBAY) is the flag carrier airline of the United Kingdom. BA has its headquarters in Waterside (Waterside (building)) near its main hub (Airline hub) at London Heathrow Airport and based on fleet size, international flights and international destinations is the largest airline in the UK. Its second hub is London Gatwick Airport. British Airways signed an agreement with Spanish carrier Iberia (Iberia (airline)) to create Europes second largest airline group. British Airways has discontinued all direct overseas flights from UK airports other than Heathrow, Gatwick and London City Airport. BAs UK passengers originating at non-London airports must now connect via London or use other airlines with direct services.

The British Airways Group was formed on 1 September 1974 through nationalisation by the Labour Government of the time. BA was formed from two large London-based airlines, BOAC (British Overseas Airways Corporation) and BEA (British European Airways), and two much smaller regional airlines, Cambrian Airways Cardiff and Northeast Airlines Newcastle upon Tyne. All four companies were dissolved on 31 March 1974 to form British Airways (BA) and almost thirteen years later, in February 1987, the company was privatised. The carrier soon expanded with the acquisition of British Caledonian in 1988 and Gatwick-based carrier Dan-Air in 1992. Despite being a primarily Boeing customer, British Airways placed a major order for Airbus aircraft in November 1998 with the purchase of 89 A320 Family aircraft. In 2007, the carrier placed its next major order, marking the start of its long-haul (flight length) fleet replacement, ordering Airbus A380s and Boeing 787s. The centrepiece of the airlines long-haul fleet is the Boeing 747-400; with 49 examples in service, British Airways is the largest operator of the type in the world.

The formation of Richard Bransons Virgin Atlantic Airways in 1984 began a tense relationship with BA. In 1993, the fierce rivalry led to "one of the most bitter and protracted libel actions in aviation history" in which British Airways apologised "unreservedly" for a ?dirty tricks? campaign against Virgin leading to them paying damages and legal costs. Until 2008 British Airways was the largest airline of the UK, measured by passenger numbers. In 2008, the airline carried 35.7 million passengers. Rival UK carrier EasyJet carried 44.5 million passengers in the same year, taking the title from British Airways.

British Airways is listed on the London Stock Exchange and is a constituent of the FTSE 100 Index. On 31 March 2009, the airline celebrated its 35th anniversary. On 12 November 2009, British Airways confirmed that it had reached a preliminary agreement to merge with Iberia (Iberia (airline)). The merger between the two carriers will create the worlds third-largest airline in terms of annual revenue. The merger was confirmed on 8 April 2010, and it is expected to be completed by the end of the year.