The Australian Bureau of Statistics has also found that Australians are getting older and becoming less religious.
The census also found that — for the first time — more of the 1.3 million migrants arriving between 2011-2016 came from Asia, not Europe.
Two-thirds of the population were born in Australia, followed by England and New Zealand.
However, the number of people born in China increased from six per cent to 8.3 since 2011, making them the third largest cohort of foreign born citizens.
Indian-born Australians increased from 5.6 per cent to 7.4, while the Philippines has swapped places with Italy to take the fifth spot.
The next largest group are from Malaysia, which has replaced Scotland as a source of migration.
The proportion of people who said they didn’t follow any religion increased to about a third, up from 16 per cent 2001.
More people identified as Aboriginal or Torres Strait Islander and they now account for 2.8 per cent of the population.
New South Wales remains the most populous state, with nearly 7.5 million people. It was followed by Victoria and Queensland.
Renters are forking out more, with the median household weekly rent rising to $335.
Meanwhile, the median weekly personal income is $662, compared to a family at $1,734.
Australians who own their properties outright fell to 31 per cent, a decline of more than 10 per cent from 25 years ago.
The number of same-sex couples increased by 39 per cent from 2011 to 46,800 now.