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.