Electoral system of Australia

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.

Elections are conducted by the Australian Electoral Commission or the respective state or territory Electoral Commission.

A person can only vote if enrolled on the appropriate electoral roll.

The earliest electoral roll in Australia dates to the 1840s, for the then colony of New South Wales.

Following federation in 1901, State electoral rolls were used for federal elections until a Commonwealth electoral roll was compiled. A permanent Commonwealth electoral roll was compiled in 1908. For some years afterwards, the States also compiled their own State electoral rolls, but these have now been discontinued except for Western Australia which maintains a separate electoral roll. Since 1984, the Commonwealth electoral roll has been compiled and maintained by the Australian Electoral Commission (AEC).

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