Entering and leaving Australia
All Australians, including dual nationals, should leave and enter Australia on their Australian passport. If you have a passport from another country for example; a British passport, you can use this for your return to the United Kingdom, but you will need your Australian passport for travel to Australia when departing the United Kingdom and entering Australia.
Those trying to enter Australia as an Australian citizen but without an Australian passport will face difficulties and delays. An Australian passport is the preferred and most conclusive proof of Australian citizenship when travelling.
International airlines have an obligation to carry only appropriately documented passengers to Australia. Appropriate documentation for Australian nationals is an Australian passport. Appropriate documentation for a foreign national is a visa to enter Australia, Australian citizens do not qualify for a visa in a foreign passport for entry to Australia. If an Australian national attempts to board a flight to Australia without an Australian passport, airlines will likely be unable to verify their claim to Australian citizenship at the time of check-in and may refuse boarding. See the Department of Immigration and Border Protection website for further information on citizenship and travel.