Just under a third of Australia's 9.8 million homes are owned outright, while more than a third are owned with a mortgage, the 2021 census has found.
The data also showed that while most people live in a family situation, nearly 900,000 live together in a group, while 2.5 million live alone.
The large majority of homes are detached, while 3.2 million dwellings have four bedrooms or more.
Launching the census results on Tuesday, the nation's deputy statistician Teresa Dickinson said the number of homes owned either outright or with a mortgage has not changed significantly since 1996.
"However the share of homes which are owned with a mortgage, rather than outright, has been growing," she told a media conference in Canberra.
"Over the last 25 years the number of homes owned outright has increased by 10 per cent, while the number owned with a mortgage has doubled."
Of the 2.9 million homes that are owned outright, 2.4 million are standalone properties, while of the 3.3 million under a mortgage, 2.7 million are detached houses.
There are 2.8 million rental households, which tenant advocacy group Better Renting estimates is 280,000 more than recorded in the 2016 census.
However, Better Renting executive director Joel Dignam said there was a concerning decrease of more than 25,000 in public housing.
"These figures show that governments aren't even providing enough public housing to keep up with population growth, let alone an increase in public housing to meet the urgent need for people who are currently couch-surfing, sleeping in their cars, or skipping meals to pay the rent," he said.
There are 23.5 million Australians living in a private dwelling, 20.1 million of whom are in a family household.
A further 871,349 people live together as a group, while 2.5 million live alone.
Of the 6.2 million people who live in a home that is owned outright, 875,176 have a weekly income of $4000 or more, while of the 9.8 million paying off a mortgage, 2.4 million are in the same wage bracket.
There are seven million people renting in Australia, of whom 926,918 have a weekly salary of between $2000 and $2999, and 712,288 have a weekly income of $4000 or more.
At the other end of the scale, there are 104,996 renters who have no income at all, the census data shows.
There are 30,053 people who are purchasing a house under a shared-equity scheme. The largest proportion of these, 2588 people, have a weekly salary of $650 to $799.
Australian Associated Press