Household projections are published by the Australian Bureau of Statistics (ABS). Australian household projections are not predictions or forecasts, but are illustrations of the change in the numbers of households that would occur if assumptions about future trends in living arrangements were to occur. The projections are derived using propensities from the Census of Population and Housing for persons to be in different living arrangements. Trends observed in the propensities over the last four Censuses are assumed to continue into the future, and applied to a projected population. Numbers of families are then derived from the projected living arrangements of the population, and numbers of households are derived from the projected numbers of families.

Three projection series are presented in Household projections, and each series reflects a different assumption about future change in peoples' living arrangements. Living arrangement information from the last four Censuses (2006, 2011, 2016 and 2021) are used to set the assumptions; assumed rates of change have been applied to the 2021 reconciled propensities to give projected propensities for the period 2022 to 2046 for each living arrangement (for each age group).

The assumptions for each of the projection series are as follows: Series I holds 2021 propensities constant over the whole period, Series II assumes the observed trend will continue at a decreasing rate, and Series III continues at the full rate of change over the whole projection period.

See ABS - Household and Family Projections, Australia for further information, including in-depth commentary and analysis, in particular, the source data Quality Declaration. Source reference Data Explorer, Projected households, Australia, 2021 to 2046.