How many states in Australia?

Australia has six states: New South Wales, Victoria, Queensland, South Australia, Western Australia, and Tasmania. The six states were formerly separate British colonies that voted in referendums in the late 1890s to federate, and they joined together as the Commonwealth of Australia on 1 January 1901.

Each state has its own constitution, parliament, premier, and supreme court, and retains the powers it held as a colony except those transferred to the Commonwealth under the federal Constitution. State parliaments are bicameral in five of the six states (Queensland abolished its upper house in 1922 and is now unicameral). State governments run schools, public hospitals, police, and roads, and they share responsibility for health funding and university regulation with the Commonwealth.

The states vary enormously in size and population. New South Wales is the most populous (about 8.4 million in 2024) and Tasmania the smallest (about 575,000). Western Australia is by far the largest in area at 2.5 million square kilometres, while Victoria is the smallest mainland state at just 227,000 square kilometres but the second most populous after New South Wales.

Australia also has two self-governing internal territories on the mainland: the Australian Capital Territory and the Northern Territory. These differ from states in that the Commonwealth Parliament can override territory laws, a power exercised most famously to overturn the Northern Territory's voluntary euthanasia law in 1997. Several external territories (Christmas Island, the Cocos (Keeling) Islands, Norfolk Island, the Australian Antarctic Territory, and others) are also under federal administration but sit outside the six-state federation.