Postcodes are used in Australia for the purposes of sorting and directing mail. All postcodes in Australia consist of exactly four numerical digits and are placed at the end of the address. Australian postcodes are allocated and managed by Australia Post.
On envelopes and postcards there are often four rectangular boxes printed in orange ink at the bottom right for the postal code digits. These are used when addressing mail by hand.
Postcodes were introduced in Australia in 1967 by the Postmaster-General's Department (PMG), the predecessor of Australia Post.Australian Postcodes are exactly four digits long, and written after the name of the city, suburb, or town, and the state or territory.