Tax file numbers

This information explains how to apply for, or enquire about, your tax file number (TFN).

What is a tax file number (TFN)?

Your TFN is a unique number we give you to help us manage tax and other government services.

We normally only issue one TFN to you during your lifetime, even if you change your circumstances such as your name or residency. You should keep your TFN secure at all times and advise us if you change your name or address so we can update your details.

For more information on: keeping your TFN secure, including lost or stolen TFNs, see How do I look after my TFN? updating your details, see More information.