Also due to immigration, the European component's share of the population rose sharply in the late 18th and 19th centuries, but is now declining as a percentage.

[33] national population Australia contains five cities (including their suburbs) that consist of over one million people.

[46] Source:[47] [56] At the time of Australian Federation in 1901, the rate of natural increase was 14.9 persons per 1,000 population.

In 1996 the rate of natural increase fell below seven for the first time, with the downward trend continuing in the late 1990s.

[61] Dutch navigators landed on the coasts of modern Western Australia and Queensland several times during the 17th century.

At that time, the indigenous population was estimated to have numbered between as few as 315,000 and as many as 1,100,000,[62][63] divided into many tribes speaking many different languages.

The total fertility rate for Aboriginal and Torres Strait Islander women was 2.17 births per woman.

At that time, the indigenous population was estimated to have been between 315,000 and 750,000,[62] divided into as many as 500 tribes speaking many different languages.

[75] Although the ABS does not collect data on race and ethnic background, various studies have put together results of the census to determine the ethnic composition of Australia, the Australian Human Rights Commission has estimated the European population at 76% of the Australian population in 2016,[76] while a media diversity study put it at 72% in 2021, the non-European proportion was 21% and 23% respectively, and the Aboriginal Australian population at 3% in both.

[77] Immigration minister Andrew Giles had pledged to incorporate a question on ethnicity into the 2026 Australian census.

[83] The following table shows Australia's population by country of birth as estimated by the Australian Bureau of Statistics in 2023.

The percentage of Australians with European backgrounds has been declining since the 1960s and 1970s, which is around the time the White Australia policy was abolished.

The next most common languages spoken at home are Mandarin Chinese (2.7%), Arabic (1.4%), Vietnamese (1.3%), and Cantonese (1.2%).

Over 250 Indigenous Australian languages are thought to have existed at the time of first European contact; fewer than 20 are still in daily use by all age groups.

The Australian Bureau of Statistics included Auslan as an option for the first time in the 2021 census when asking which language was used at home.

Multicultural immigration since the Second World War has led to the growth of non-Christian religions, the largest of which are Islam (3.2%), Hinduism (2.7%), Buddhism (2.4%), Sikhism (0.8%), and Judaism (0.4%).

[73] The Australian Bureau of Statistics 2001 Census Dictionary statement on religious affiliation states the purpose for gathering such information: Data on religious affiliation are used for such purposes as planning educational facilities, aged persons' care and other social services provided by religion-based organisations; the location of church buildings; the assigning of chaplains to hospitals, prisons, armed services and universities; the allocation of time on public radio and other media; and sociological research.Historically, Australian Aboriginal religion and mythology was the prevalent belief system in Australia until around 1840, when European Australians first outnumbered indigenous Australians.

[99] As in many Western countries, the level of active participation in religious services is lower than would be indicated by the proportion of the population identifying themselves as affiliated with a religion; weekly attendance at Christian church services is about 1.5 million, or about 7.5% of the population.

[100] Christian charitable organisations, hospitals and schools play a prominent role in welfare and education services.