A redistribution of electoral divisions is undertaken in accordance with Part IV of the Electoral Act. Redistributions ensure—as close as practical—that an equal number of electors are in each electoral division for a state or territory. Each member in the House of Representatives represents an electoral division.
A redistribution is required when:
there is a change in the number of members in the House of Representatives to which a state or territory is entitled
the number of electors in more than one third of the electoral divisions of a state or the Northern Territory (or one division in the ACT) deviates from the average divisional enrolment of that state or territory by plus or minus 10 per cent for a period of more than two months
seven years have elapsed since the last redistribution
Redistributions are conducted by two bodies:
a redistribution committee, which is responsible for making a proposed redistribution
an Augmented Electoral Commission, which determines the final names and boundaries of electoral divisions
In 2019–20 there were no redistributions of electoral divisions in any state or territory, and the number of members remained at 151 (see figure 2).