The average Australian household is getting smaller, but slowly. Across three Censuses the published average went from 2.6 people in 2011 and 2016 to 2.5 in 2021. The clearest change is at the small end: one-person households rose from 24.3% of all households to 25.6%, almost all of it between 2016 and 2021, while households of five or more fell from 10.0% to 9.6%. The ABS’s own projections do not agree on whether the trend continues.
Australian Bureau of Statistics, Census of Population and Housing, 2011, 2016 and 2021.
What household size measures
A household is one or more people who usually live in the same private dwelling. Average household size is the number of people usually living in occupied private dwellings divided by the number of those dwellings. The only full count comes from the Census, held every five years. Results from the 2026 Census are not yet published, so the most recent measured change is between 2016 and 2021. The Australian Bureau of Statistics (ABS) publishes the average to one decimal place, and this piece does not calculate it more finely or estimate it between Censuses.
From 2.6 to 2.5
Nationally, the average was 2.6 people per household in 2011 and 2016 and 2.5 in 2021. At one decimal place, a change of one-tenth can reflect a much smaller underlying shift, so the distribution of households by size, which the Census counts exactly, gives the clearer picture.
Households by number of usual residents, 2011 and 2021
Share of occupied private dwellings. Source: ABS, Census of Population and Housing 2021, time series table T15.
Two-person households remained the most common, about a third of the total in each Census. One-person households went from 24.3% in 2011 to 24.4% in 2016 and 25.6% in 2021. Their number grew by 17% between 2016 and 2021 alone, and by 26% over the decade, against 20% for all households. Households of five or more people fell from 10.2% in 2016 to 9.6%.
The Census household composition count tells the same story from another angle: lone-person households were 23.1% of all households in 2011 and 24.2% in 2021, while couples with children fell from 30.7% to 29.7%. That table counts every household, including those that could not be classified, so its shares are a little lower than the size table’s.
By state and territory
In 2021 the average ranged from 2.8 in the Northern Territory to 2.4 in South Australia and Tasmania. It was lower in 2021 than in 2011 in five jurisdictions, and the same in New South Wales, South Australia and Tasmania, where Tasmania’s dipped to 2.3 in 2016 and returned to 2.4. The share of one-person households rose in every state and territory, and in 2021 was highest in Tasmania and lowest in the Northern Territory.
One-person households by state and territory, 2021
Share of occupied private dwellings with one usual resident. Source: ABS, Census of Population and Housing 2021, time series table T15.
| Jurisdiction | Average size 2011 | 2016 | 2021 | One-person households 2011 | 2021 |
|---|---|---|---|---|---|
| Australia | 2.6 | 2.6 | 2.5 | 24.3% | 25.6% |
| New South Wales | 2.6 | 2.6 | 2.6 | 24.2% | 25.0% |
| Victoria | 2.6 | 2.6 | 2.5 | 24.5% | 25.9% |
| Queensland | 2.6 | 2.6 | 2.5 | 22.8% | 24.7% |
| South Australia | 2.4 | 2.4 | 2.4 | 27.9% | 28.5% |
| Western Australia | 2.6 | 2.6 | 2.5 | 23.8% | 25.4% |
| Tasmania | 2.4 | 2.3 | 2.4 | 28.0% | 29.0% |
| Northern Territory | 2.9 | 2.9 | 2.8 | 21.9% | 23.8% |
| Australian Capital Territory | 2.6 | 2.5 | 2.5 | 23.4% | 25.7% |
Average household size: persons usually resident per occupied private dwelling, as published by the ABS to one decimal place. One-person households: share of occupied private dwellings with one usual resident. Source: ABS, Census of Population and Housing 2021, time series tables T02 and T15.
What the projections show
The ABS’s household projections, based on the 2021 Census, run to 2046 under three series with different assumptions. They start from 9.99 million households in 2021, a different base from the Census count of occupied private dwellings. Under Series I, lone-person households rise from 26.4% of all households to 28.4% by 2046; under Series II to 27.7%; under Series III the share falls to 25.9%. These are projections of what would happen if each set of assumptions held, not forecasts, and they disagree on direction.
Projected lone-person households as a share of all households, 2021 to 2046
ABS Household and Family Projections, Australia, 2021 to 2046, Series I, II and III. Source: ABS.
What this does not show
Census counts are five years apart, and the 2021 Census was held during pandemic restrictions, which may have affected who was living where on Census night. Household size says nothing about why people live alone or together, and no link to housing demand or prices is drawn here. The age shifts behind part of this change are covered in The Age Pyramid, 2011 to 2026 and Fewer Working-Age People per Older Australian. The Demographic Analysis series carries the node readings.
Findings are presented on the basis of data and evidence alone.
