Tax file numbers

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

Note: Tax file numbers (NAT 1753) is also available as a complete product: as a downloadable Portable Document Format (PDF, 100KB), or paper product.

What is a tax file number (TFN)?

A TFN is a unique number we issue to individuals and organisations to help us administer tax and other Australian Government systems.

We 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 see How do I look after my TFN? updating your details see More Information.

Last Modified: Wednesday, 12 November 2008