Expansion of the A-League

The expansion of the A-League has occurred several times since the league began play in 2005. The A-League was established as the top soccer division in the Australian league system, and the only professional and national league of the sport. It was founded in 2004 with eight teams and has since expanded into new markets across Australia and New Zealand. The league is currently contested by 10 teams, although a total of 13 have competed at some stage in its short history

An expansion of at least 2 teams for the 2018–19 A-League season have been planned.

When founding the A-League in early 2004, Football Federation Australia (FFA) was very cautious in selecting who was to be part of the new league. FFA decided upon a 'one city - one team' principle in order to protect the initial development of the foundation clubs.

The initial eight teams selected were Adelaide United FC, Brisbane Roar FC (formerly Queensland Roar FC), Central Coast Mariners FC, Melbourne Victory FC, Newcastle Jets FC, Perth Glory FC, Sydney FC and New Zealand Knights FC. Of these 8 clubs, only the New Zealand Knights have failed to survive, folding after the 2006–07 season.

Before the introduction of the A-League, FFA chairman Frank Lowy speculated that he hoped to expand the league into other cities, mentioning Canberra, Hobart, Wollongong, Coffs Harbour, Geelong, Bendigo, Cairns, Ballarat, Albury–Wodonga, Launceston, Christchurch, Auckland, Sunshine Coast and possibly Darwin.

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