The latest projections from the Australian Bureau of Statistics shows Australia's population will double in the next 60 years, driven by strong increases in Victoria and New South Wales.
The bureau is projecting the population will soar from just under 23 million people to 46 million by 2075.
Western Australia is expected to have the largest rise, while Tasmania is the only state that is expected to see a decline in population.
The bureau's director of demography Bjorn Jarvis says by 2028 Perth will overtake Brisbane as Australia's third-biggest city, with 3 million people.
"And then 10 years later, the Australian Capital Territory [will overtake] Tasmania," he said in a statement.
"Melbourne and Sydney should be neck and neck by 2053, with 7.9 million people each.
"By 2040, Western Australia's population is projected to almost double in size, from 2.4 million people in 2012 to 4.7 million.
"Queensland will have gone from 4.6 million people to 7.3 million, and the Australian Capital Territory will have grown from 375,000 people to 586,000."
The Northern Territory's population will increase by 51 per cent to 360,000, while Victoria's population will grow by 50 per cent 8.4 million.
In New South Wales, the population will climb by 35 per cent to 9.9 million.
Tasmania's population is tipped to level out by 2040, and then begin falling.
www.abc.net.au
