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Following a double dissolution election, such as the one held in July 2016, all 76 senators are re-elected. The Senate must then agree on a method to decide which senators will serve a six-year term and which will serve a three-year term.
Normally, because state senators are elected on a rotating basis and for a six-year term, half these senators are elected in a general election with the House every three years. The terms of the four territory senators are the same as the members of the House of Representatives.
Section 13 of the Australian Constitution requires that the rotation of the Senate must be re-established following a double dissolution election. Under a motion agreed to by the Senate when it first met after the election, senators who received the largest quota of votes or, in other words, won the first six spots in each state, will serve six-year terms. Those elected in the 7th to 12th spots will serve three-year terms.
To see which senators will serve three years and which will serve six years after the 2016 election, visit the Senate Daily Summary page on the Australian Parliament House website and click on ‘Wednesday 31 August’. This will take you to a list of the writs for each state and the order in which senators were elected.