There are different pathways to become an Australian citizen. For example, permanent residents of Australia, or citizens of New Zealand, may qualify for Australian citizenship by conferral if they meet the requirements that apply to their citizenship category or pathway. People who were born overseas to an Australian citizen parent, people who were adopted outside of Australia by an Australian citizen, people born in Papua before independence in 1975, as well as people who used to be Australian citizens in the past may also be eligible for Australian citizenship.
If you are permanent resident of Australia wishing to apply for Australian citizenship, you will need to show that, at the time when you apply, you have been living in Australia on a valid visa for the past 4 years, and you have not been away from Australia for more than 12 months in total in the past 4 years, including no more than a total absence from Australia of 90 days in the past 12 months.
Whilst children under 16 years of age may not have to meet the general residence requirement, they must be Australian permanent residents in order to be eligible for citizenship in Australia.
To be eligible for Australian citizenship by conferral, citizens of New Zealand must also show that they hold an Australian permanent resident visa, or were present in Australia on 26 February 2001 on a Special Category visa, or that they spent a total of 12 months in Australia on a Special Category visa in the 2 years before 26 February 2001 if they were outside Australia on that date, or they need to hold a Centrelink certificate issued before 26 February 2004 that states they were living in Australia on a particular date.
Some of the further requirements for the grant of Australian citizenship pertain to character, English language skills, and knowledge of Australia.