It is incredibly common to lose track of your Tax File Number (TFN), especially if you haven’t lodged a tax return in a while or have recently changed jobs. The most important thing to know is that your TFN is yours for life. Even if you move states, change your legal name, or go overseas for years, the Australian Taxation Office (ATO) never changes your number.

You should never submit a new TFN application if you have already been issued one in the past. Doing so can trigger a system flag for duplicate identities, causing major processing delays and freezing your active tax records.

Instead, retrieving your existing number digitally takes less than two minutes via myGov.

How to Locate Your TFN via myGov

If you have previously linked your myGov account to the Australian Taxation Office (ATO), your secure dashboard holds your tax file number ready for instant viewing.

Step 1: Log In and Select Your Service

Navigate to the official myGov portal (my.gov.au) and complete your login using your email or username alongside your two-factor authentication code. On your main member homepage under “Linked Services”, click directly on the Australian Taxation Office (ATO).

Step 2: Access Your Profile Details

Once the secure ATO portal loads, look at the top menu bar. Locate the tab labeled My profile, click it to open the drop-down menu, and select Personal details.

Step 3: View the Number

Your 9-digit Tax File Number will be displayed clearly on this screen under your legal name and date of birth. You can securely copy it down from this window.

What If Your myGov Account Isn’t Linked to the ATO?

If your myGov account is active but you never linked the tax office to it, you will need to establish that connection first to view your profile.

To link the ATO, click “View and link services” from your myGov home screen, select the Australian Taxation Office, and click “Link”. Because the system needs to verify that you are who you say you are, it will ask you two security questions based on historical data only you would know. You can use details from:

• A Notice of Assessment (NOA) issued within the last few years.
• A recent superannuation account statement showing your member number and fund details.
• Your bank account details where you have previously received an ATO tax refund.
• An income statement or PAYG payment summary from a past employer.

Once these security questions are cleared, the connection is immediate, and you can follow the profile steps above to view your permanent TFN.

Fast Back-Up Methods If myGov Fails

If you cannot access your myGov account or lack the data required to link the ATO online, you still do not need to reapply. You can find your existing TFN hiding on several documents you likely already have:

• Your Super Fund App or Statement: Log into your superannuation fund portal (like AustralianSuper, Hostplus, etc.). Because super funds require your TFN to accept concessional contributions, the number is always listed under your personal profile or on your annual statements.
• The ATO App: If you have the official ATO smartphone app downloaded and configured with a fast login (like FaceID or your myID), tapping “My details” displays your number on screen immediately.
• Historic Tax Paperwork: Search your computer files or email inbox for an old PDF download of a “Notice of Assessment” or past tax returns prepared by an accountant. Your TFN sits prominently at the top of these documents.

If all digital paths fail, call the ATO Individuals line directly. Once you pass an over-the-phone identity check using your passport or driver’s license, the operator will read out your original number.