Population aged between 18 and 25 in Australia - Data and Analysis (1971-2033)

IBISWorld forecasts the population aged between 18 and 25 to rise by 2.0% during 2025-26, to reach 2,976,878 people. This growth is expected to be influenced by a large disparity in the number of Australian-born citizens turning 18 compared to those turning 26, placing upwards pressure on the population of 18 to 25 year olds. Expansions in net migration will also contribute to an expansion in the population across all ages, including 18 to 25 year olds.The long-term growth of the population aged between 18 and 25 has been supported by lower child mortality rates. Child mortality has declined significantly over the past 25 years, leading to a greater number of people surviving long enough to enter this population segment. Over the period, growth in the population of this age demographic has been supported by expansions in birth rates between 2000-01 and 2007-08. This trend has led to an expansion in the number of people entering this demographic.Migration levels also affect the size of this age demographic. Strong growth in migration levels can have a positive effect on the size of this age demographic, as many migrants are young people entering the country for education or job opportunities. Despite a temporary disruption during the pandemic, net migration has remained an important driver of this population segment over the past five years. In particular, the spike in international students during 2022-23 and 2023-24 contributed to the demographic expanding at the fastest rate on record over the two year period. As growth in international university students has tapered off in 2024-25 and 2025-26, the growth rate of this segment has slowed but remained above historical levels. Overall, IBISWorld forecasts the population aged between 18 and 25 to fall at a compound annual rate of 3.1% over the five years through 2025-26.