At the end of March 2026 there were 27.2 Australians aged 65 and over for every 100 aged 15 to 64, up from 20.5 in 2011. Put the other way, there were 3.67 people of working age for each older person, against 4.89 fifteen years earlier. The ratio has risen in all but three quarters since 2011. How fast it rose moved with migration: it climbed fastest in the year the borders closed and barely moved while arrivals were at their highest.
The node reading compares the September 2025 ratio with its average since 2011. The ratio in this article is recalculated from the latest ABS estimates, which carry the March 2026 quarter.
What the ratio measures
The old-age dependency ratio is the number of people aged 65 and over for every 100 people aged 15 to 64. It is a demographic ratio, built only from ages. It does not measure who works: many people over 65 are in paid work, and many aged 15 to 64 are studying, caring for others or otherwise not employed. What it shows is the balance between two broad age groups, and how the population’s age structure is shifting.
The figures here are the Australian Bureau of Statistics’ (ABS) quarterly estimates of the resident population by single year of age, from March 2011 to March 2026.
From 20 to 27
The ratio was 20.45 in March 2011 and 27.24 in March 2026, the highest in the period. Its average over March 2011 to September 2025 was 23.98. It rose in every quarter except three, all in 2022 and 2023.
People aged 65 and over per 100 aged 15 to 64, 2011 to 2026
Quarterly, estimated resident population. Dotted line: the average from March 2011 to September 2025. Source: ABS, Quarterly Population Estimates (ERP), by State/Territory, Sex and Age.
Both groups grew. The number aged 65 and over rose by 62%, from 3.06 million to 4.95 million, while the number aged 15 to 64 rose by 21%, to 18.18 million. People aged 65 and over went from 13.8% of the population to 17.7%.
Population by age group, indexed to March 2011
March 2011 = 100. Quarterly, estimated resident population. Source: ABS, Quarterly Population Estimates (ERP), by State/Territory, Sex and Age.
The pace moved with migration
From 2012 to 2019 the ratio rose by a steady 0.4 to 0.5 each year. The rise then accelerated to 0.67 in the year to March 2020 and 0.92 in the year to March 2021, when net overseas migration turned negative. It nearly stopped in the years to March 2023 and 2024, rising by 0.02 and 0.11, as net overseas migration reached its highest in the period. In the year to March 2026 it rose by 0.43, back within its earlier range. The timing matches; this piece does not estimate how much of each change migration accounts for. How migration and natural increase have made up population growth is covered in Births, Deaths and Arrivals, and the growth rate itself in The Population Growth Rate Since 2011.
Rise in the ratio over the year to each March quarter
Change in people aged 65 and over per 100 aged 15 to 64 over the four quarters to March. Source: ABS, Quarterly Population Estimates (ERP), by State/Territory, Sex and Age.
The oldest group
People aged 85 and over numbered 621,046 in March 2026, up from 400,631 in 2011, and rose from 1.80% to 2.22% of the population. That is growth of 55%, slower than for the 65-and-over group as a whole. The large cohorts born from 1946 onward reached 65 during the period; the oldest of them turned 80 in 2026. The number aged 100 and over rose from 3,102 to 8,373.
| March quarter | Aged 65 and over | Aged 15 to 64 | Aged 85 and over | 65+ per 100 aged 15–64 | Aged 15–64 per person 65+ |
|---|---|---|---|---|---|
| 2011 | 3,064,088 | 14,980,315 | 400,631 | 20.45 | 4.89 |
| 2012 | 3,182,855 | 15,171,548 | 417,326 | 20.98 | 4.77 |
| 2013 | 3,301,330 | 15,380,309 | 434,005 | 21.46 | 4.66 |
| 2014 | 3,416,051 | 15,564,067 | 451,060 | 21.95 | 4.56 |
| 2015 | 3,527,443 | 15,731,088 | 466,134 | 22.42 | 4.46 |
| 2016 | 3,642,719 | 15,907,355 | 479,815 | 22.90 | 4.37 |
| 2017 | 3,759,913 | 16,129,001 | 489,561 | 23.31 | 4.29 |
| 2018 | 3,877,561 | 16,329,790 | 496,826 | 23.75 | 4.21 |
| 2019 | 4,002,019 | 16,541,630 | 506,582 | 24.19 | 4.13 |
| 2020 | 4,155,281 | 16,713,811 | 516,829 | 24.86 | 4.02 |
| 2021 | 4,284,705 | 16,622,037 | 532,276 | 25.78 | 3.88 |
| 2022 | 4,405,152 | 16,748,619 | 545,940 | 26.30 | 3.80 |
| 2023 | 4,529,635 | 17,208,113 | 558,421 | 26.32 | 3.80 |
| 2024 | 4,666,117 | 17,653,280 | 577,730 | 26.43 | 3.78 |
| 2025 | 4,805,230 | 17,926,008 | 599,182 | 26.81 | 3.73 |
| 2026 | 4,950,368 | 18,176,145 | 621,046 | 27.24 | 3.67 |
Estimated resident population, persons, Australia, at the end of each March quarter. Source: ABS, Quarterly Population Estimates (ERP), by State/Territory, Sex and Age.
What this does not show
The ratio counts ages, not work, income or health, and says nothing about how older Australians are housed; no link to housing demand, prices or rents is drawn here. The estimates for recent quarters are preliminary and are revised as fuller data arrive. The Demographic Analysis series carries the node readings.
Findings are presented on the basis of data and evidence alone.
