Australia’s population grew by a quarter between March 2011 and March 2026, but not evenly across ages. The number aged 75 to 79 rose by 86% and people in their early thirties by 37%, while children under five rose by just 3.2%. The median age went from 37.2 to 38.5 years, and the most common single age from 39 to 31: the population is older at the top and younger at its peak.
Estimated resident population by single year of age, Australian Bureau of Statistics, March quarters 2011 and 2026.
Reading an age pyramid
An age pyramid shows how a population is spread across ages. Each bar is a five-year age group, men on the left and women on the right, measured as a share of the whole population. The figures here are the Australian Bureau of Statistics’ (ABS) quarterly estimates of the resident population by single year of age, for the March quarters of 2011 and 2026.
Australia’s population by age and sex, March 2011 and March 2026
Share of the whole population in each five-year age group. Bars: March 2026. Lines: March 2011. Source: ABS, Quarterly Population Estimates (ERP), by State/Territory, Sex and Age.
Three shifts stand out. The top of the pyramid has widened, as the large cohorts born from 1946 onward moved past 65. The bulge in the middle has moved down the ages: the most common single age was 39 in 2011 and is 31 now, and the groups from 30 to 39 grew faster than the population as a whole. And the base has narrowed as a share of the total, because the number of young children has barely grown.
Where the growth went
The population grew by 25.4% over the fifteen years. Seven of the eighteen age groups grew faster than that: the two from 30 to 39, and every group from 65 upward. The fastest was 75 to 79, up 86.3%. The slowest were children under five, up 3.2%, and people aged 45 to 49, up 9.0%.
| Age group | March 2011 | March 2026 | Change | Share 2011 | Share 2026 |
|---|---|---|---|---|---|
| 0–4 | 1,456,656 | 1,503,701 | 3.2% | 6.54% | 5.39% |
| 5–9 | 1,380,537 | 1,598,008 | 15.8% | 6.20% | 5.72% |
| 10–14 | 1,387,162 | 1,692,928 | 22.0% | 6.23% | 6.06% |
| 15–19 | 1,457,812 | 1,734,638 | 19.0% | 6.55% | 6.21% |
| 20–24 | 1,611,680 | 1,846,433 | 14.6% | 7.24% | 6.61% |
| 25–29 | 1,650,594 | 2,051,633 | 24.3% | 7.41% | 7.35% |
| 30–34 | 1,526,738 | 2,085,200 | 36.6% | 6.86% | 7.47% |
| 35–39 | 1,580,948 | 2,042,614 | 29.2% | 7.10% | 7.32% |
| 40–44 | 1,574,526 | 1,948,470 | 23.7% | 7.07% | 6.98% |
| 45–49 | 1,545,190 | 1,684,551 | 9.0% | 6.94% | 6.03% |
| 50–54 | 1,485,505 | 1,666,192 | 12.2% | 6.67% | 5.97% |
| 55–59 | 1,328,973 | 1,589,019 | 19.6% | 5.97% | 5.69% |
| 60–64 | 1,218,349 | 1,527,395 | 25.4% | 5.47% | 5.47% |
| 65–69 | 942,947 | 1,411,747 | 49.7% | 4.23% | 5.06% |
| 70–74 | 722,031 | 1,208,811 | 67.4% | 3.24% | 4.33% |
| 75–79 | 556,254 | 1,036,393 | 86.3% | 2.50% | 3.71% |
| 80–84 | 442,225 | 672,371 | 52.0% | 1.99% | 2.41% |
| 85+ | 400,631 | 621,046 | 55.0% | 1.80% | 2.22% |
| All ages | 22,268,758 | 27,921,150 | 25.4% | 100.00% | 100.00% |
Estimated resident population, persons, Australia. Source: ABS, Quarterly Population Estimates (ERP), by State/Territory, Sex and Age.
The median age
Half the population is older than the median age and half younger. It was 37.2 years in March 2011 and stayed within about a tenth of a year of that until 2017. It then rose, most quickly between 2019 and 2021, to 38.5 in March 2022; eased to 38.3 in March 2023 and 38.3 in March 2024; and was 38.5 in March 2026, the highest in the period. The comparison uses March quarters only, because the median moves a little within each year.
Median age, March quarters 2011 to 2026
Years. Calculated from the estimated resident population by single year of age, treating each year of age as spread evenly across the year. Source: ABS, Quarterly Population Estimates (ERP), by State/Territory, Sex and Age.
The broad groups
Of six broad age groups, three took a larger share of the population in 2026 than in 2011: 25 to 44, 65 to 84, and 85 and over. People aged 65 and over went from 13.8% of the population to 17.7%. Children under 15 fell from 19.0% to 17.2%, and people aged 45 to 64 from 25.0% to 23.2%. Among people aged 85 and over, women were 66% in 2011 and 59% in 2026.
Share of the population by broad age group, March 2011 and March 2026
Per cent of the estimated resident population. Source: ABS, Quarterly Population Estimates (ERP), by State/Territory, Sex and Age.
What this does not show
These are counts of people by age; they say nothing about where people live, how they are housed or what they earn, and no inference about housing demand is drawn here. The ratio of older to working-age people is covered in Fewer Working-Age People per Older Australian, and the births, deaths and migration that shape the pyramid in Births, Deaths and Arrivals. Estimates for recent quarters are preliminary and are revised as fuller data arrive.
Findings are presented on the basis of data and evidence alone.
