[3] The total population of the Commonwealth of Australia was counted as 25,422,788, an increase of 8.6 per cent or 2,020,896 people over the previous 2016 census.

[2][better source needed] An independent report from Lateral Economics found that for every $1 of investment on the census, $6 of benefits are created in the Australian economy.

Censuses stored by the NAA cannot by accessed, amended, or retrieved by anyone, including courts and tribunal, until their release, the first of which will occur in 2100.

[10] The 2020 Census Test occurred on 27 October 2020 with around 100,000 households from Sydney, Adelaide, Darwin, and Canberra, as well as communities in Karratha, Warrnambool, and Alice Springs Town Camps.

[11] Every census, the ABS makes a recommendation to the Australian Government on the topics to be included, based on the benefit that data would provide to Australia.

The total population of Australian as counted in the 2021 census by state and external territories are:[4][16][17][18][19] Of all residents over two-thirds (72.4% or 18,235,690) were born in Australia.