Notes on the data: Aboriginal and Torres Strait Islander people, age distribution

2021 estimated resident Aboriginal population, all ages, by 5-year age group (0-4 years to 65+ years) or by broad age group (0-4, 5-14, 15-24, 25-44, 45-64, 65+ years)


Policy context: The proportions of the total estimated resident population in 2021 who were Aboriginal and/or Torres Strait Islander people (in this atlas collectively referred to as Aboriginal) varies greatly by location, from 30.7% in the Northern Territory to 1.2% in Victoria. Aboriginal people represent the largest proportion of the populations in Greater Darwin (13.2%) and in the remainder of the Northern Territory (56.9%). The next largest proportion was in Western Australia, at 11.4% outside of Perth [1].

However, the largest numbers of Aboriginal people in 2021 were in New South Wales (339,710, with 111,075 in Greater Sydney, 36,745 in Illawarra, Newcastle and Lake Macquarie and 191,890 in the remainder of New South Wales); and in Queensland (273,119, with 87,940 in Greater Brisbane, 40,284 in Gold Coast and Townsville, and 144,895 in the remainder of Queensland). The estimated resident populations in Darwin and in the remainder of the Northern Territory were 19,464 and 57,023, respectively [1].

The Aboriginal and Torres Strait Islander population is considerably younger than the non-Indigenous population. In 2021, the median age for this population was 24 years, 14.9 years less than the national median age of 38.9 years for the non-Indigenous population [2]. One in three (33.1%) Aboriginal people were estimated to be aged less than 15 years, while just 5.4% were aged 65 years and over (and although very low, this is higher than in 2011 or 2016, when the proportions was 3.8% and 5.1%, respectively) [2].


  1. Australian Bureau of Statistics (ABS), estimated resident population (produced as a consultancy for PHIDU), 30 June 2021.
  2. Australian Bureau of Statistics, Estimates of Aboriginal and Torres Strait Islander Australians: Final 2021 Census-based estimated resident population of Aboriginal and Torres Strait Islander and non-Indigenous Australians for various geographies, accessed 29 November 2023. Available from

Notes: PHIDU publishes Aboriginal population by age and sex for Population Health Areas (PHAs), Local Government Areas (LGAs) and Indigenous Areas (IAREs), and also uses these populations as a denominator when calculating percentages and rates for a large number of indicators for PHAs and IAREs.

As the Australian Bureau of Statistics (ABS) does not publish ERP by age and sex for the Aboriginal population, or by Indigenous status, for PHAs, LGAs or IAREs, PHIDU entered into a contract with the ABS to produce these data. Due to small populations in some areas, the ABS could only estimate the population by age and sex by Indigenous status for the following age groups:

  • PHA and LGA: 0-14, 15-24, 25-34, 35-44, 45-54 and 55+ years
  • IARE: 0-4, 5-9, 10-14, 15-19, 20-24, 25-29, 30-34, 35-39, 40-44, 45-49, 50-54, 55-59, 60-64 and 65+ years

The all-age totals for LGAs and IAREs are consistent with those published by the ABS.


Geography: Data available by Indigenous Area, Primary Health Network, Quintile of socioeconomic outcomes (based on IRSEO) and Remoteness Area


Numerator: Aboriginal male, female and total estimated resident population (ERP) by 5-year age group: 0-4 years to 65+ years or by broad age group: 0-4, 5-14, 15-24, 25-44, 45-64, 65+ years


Denominator: Total Aboriginal males, females or persons, ERP


Detail of analysis: The age group as a percentage of the total Aboriginal population for males, for females and for persons


Source: ABS estimated resident population (produced as a consultancy for PHIDU), 30 June 2021.


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