More than eight million Australians are living with long-term health conditions, two million of whom suffer mental health, arthritis or asthma.
Women are more likely to report having a long-term health condition, with 34 per cent suffering at least one, compared to 30 per cent of men.
These statistics are among the data collected for the 2021 census, which was released on Tuesday.
Mental health was one of the most commonly reported conditions across both genders, while females commonly reported arthritis and men reported asthma.
Almost 63 per cent of people over the age of 65 reported at least one long-term health condition, compared to 22 per cent of those aged 15 to 34-years-old.
More than 2.2 million Australians suffer long-term mental health issues, more than 2.1 million live with arthritis and just over two million live with asthma.
Australians under the age of 14 were the most likely to have asthma.
More than half of census respondents born in Greece and Italy reported having one or more condition.
Statistician David Gruen said the data, released by the ABS, provides the first comprehensive snapshot of Australia's long-term health conditions.
"This is critical data to inform planning and service delivery decisions about how treatment and care is provided," Dr Gruen said.
"Census data will help provide a more detailed picture of Australians' health (and) complements existing ABS health surveys by providing additional insights about the communities that require services to support complex health needs."
More than 4.8 million people said they suffered one of the 10 long-term conditions listed in the census, 1.5 million reported living with two, and 750,000 have three.
An additional one million people had at least one other long-term condition outside the top 10.
More detailed health and welfare data is due to be released by the ABS on Tuesday.
Australian Associated Press
Sign up for our newsletter to stay up to date.