Vehicle registration plates of Australia

Australian vehicle number plates are issued by the states and territories, the Commonwealth government, and the armed forces of Australia. The plates are associated with a vehicle and generally last for the time the vehicle remains registered in the state, though as they become unreadable (or for other reasons) they may be recalled or replaced with newer ones.

From the 1970s until the late 1990s, most Australian plates were of the form xxx·xxx (with x being either letters or numbers)—for example, aaa·nnn in Victoria, New South Wales, South Australia and the Australian Capital Territory; naa.nnn in Western Australia, where the starting number was between six and nine; and nnn.aaa in Queensland. More recently as these series have reached the limit of their capacity, different states and territories have chosen different continuations, so the commonality with respect to format is at an end. The most recent adoption of a new sequence plate is in the state of Victoria, which from 2013 issues plates in the format naa.naa. Nevertheless, standard issue plates have the same dimensions regardless of their state-of-issue so there remains an element of consistency between them.

From 1951–2, Australian automobiles were to adopt a broad scheme across all states and territories for vehicle number plates. Both NSW and Victoria had previously issued plates with 2-letter, 3-digits, white on a black background. However, while implemented, this was not entirely popular as some states and territories preferred their own identity reflected on their vehicles instead. They were 'meant' to use the following proposed scheme:

Western Australia deemed itself too large to fit into the proposed scheme and adhered to one of its own devising; plates in the Iaa-nnn series were to be skipped (as a capital I was believed to be easily mistaken for a number 1). This allowed the two populous states with greater registrations of vehicles 6 letter-series each (NSW had A-F, Victoria G-H and J-M), and others with 3 letter-series (Queensland N-Q, South Australia R-T, Western Australia was allocated U-V). Tasmania was only given one, W, due to its size, and the ACT Y. Z was for federal government department use Australia-wide, the 2nd letter reflecting the commonwealth department.

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