Australian electoral system

The Australian electoral system has evolved over 150 years of democratic government, including through the Australian Parliament, instituted in 1901. The present-day federal parliament has a number of distinctive features including compulsory voting, with majority-preferential instant-runoff voting in single-member seats to elect the lower house, the House of Representatives, and the use of the single transferable vote proportional representation system to elect the upper house, the Senate.

Federal elections and referendums are conducted by the Australian Electoral Commission. State and local government elections are overseen by separate Electoral Commissions in each state and territory: New South Wales elections are conducted by the New South Wales Electoral Commission; in Queensland it is the Electoral Commission of Queensland; in Victoria it is the Victorian Electoral Commission; in South Australia it is the Electoral Commission of South Australia; in Tasmania it is the Tasmanian Electoral Commission; in Western Australia it is the Western Australian Electoral Commission; in the Northern Territory it is the Northern Territory Electoral Commission; and in the Australian Capital Territory it is the Australian Capital Territory Electoral Commission.

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