Net overseas migration

What is net overseas migration?

Net overseas migration is the net gain or loss of population through immigration to Australia and emigration from Australia.

Being an immigrant or an emigrant who adds to, or reduces, the population size is based around the concept of Australia being the usual place of residence for some period. That period is defined to be either in or out of Australia for at least 12 months within a 16 month period (the so-called ‘12/16 month rule’).


  • an incoming international traveller who stays in Australia for 12 months or more within a 16 month period, and who is not currently counted in Australia’s population, is defined to be a net overseas migration (NOM) arrival.
  • an outgoing traveller who is subsequently absent from Australia for 12 months or more within a 16 month period, and who is currently counted within the population is defined to be a NOM departure.

Net overseas migration, the net gain or loss, is the difference between NOM arrivals and NOM departures. NOM arrivals are added to the population count whilst NOM departures are subtracted from the population count.

Being defined as a NOM arrival or departure in Australia applies regardless of nationality, citizenship or legal status. It applies whether the traveller is on a permanent or temporary visa (such as students or skilled migrants), as well as to both New Zealand and Australian citizens.

Net overseas migration over time

NOM peaks and troughs

Throughout Australia’s history, NOM has almost always been positive, fluctuating over time with changes in policy, economic conditions and global movements of people.

Since 1982, the level of NOM reached a peak in 2008 (315,700 people), which is associated with the height of the mining boom and a rapid, but temporary, increase in international students in Australia. Major troughs in NOM are generally associated with downturns in the Australian economy.

Net overseas migration, 1985 to 2020

Source: Australian Bureau of Statistics, National, state and territory population

Which countries do migrants to Australia come from?

At the time of Federation in 1901, Australia’s population was overwhelmingly derived from European countries. However, this has changed over time, particularly in the last 20 years. According to the 2016 Census, a greater proportion of people born overseas are now from Asia rather than from Europe. However, more of Australia’s residents still have European ancestry.

England remains the top source country for those born overseas, despite falling as a share of the population since the late 1990s. Meanwhile, China and India have become the second and third ranked source countries

Top 10 countries of birth, 1999 and 2019
  1999 2019
Rank Country of birth Share of population Country of birth Share of population Median age
1 England 5.0 England 3.9 57
2 New Zealand 1.8 China 2.7 34
3 Italy 1.3 India 2.6 34
4 Vietnam 0.9 New Zealand 2.2 44
5 Scotland 0.8 Philippines 1.2 40
6 China 0.7 Vietnam 1.0 47
7 Greece 0.7 South Africa 0.8 44
8 Germany 0.6 Italy 0.7 72
9 Philippines 0.6 Malaysia 0.7 40
10 Netherlands 0.5 Sri Lanka 0.6 41
  All overseas born 23.1 All overseas born 29.7 43
  Australian born 76.9 Australian born 70.3 34

Source: Australian Bureau of Statistics, Migration, Australia