- Your TFN is permanent, it never changes regardless of jobs, states, or even leaving Australia. Never apply for a new one if you’ve lost it; just retrieve your existing one through myGov.
- The fastest way to find your TFN is through myGov; log in, select ATO, then “Find my TFN.” Most people are done in under two minutes.
- Without a TFN, employers and banks must withhold tax at 47% but any excess withheld can be claimed back when you lodge your return.
Wondering how to find your tax file number? You’re not alone, it’s one of the most searched tax questions in Australia, and usually comes up at the worst possible moment. A new employer needs it before your first pay run. Your bank is asking for it. Your tax return is due.
The good news is you almost certainly already have one. A TFN is a permanent, lifelong number, it doesn’t change when you change jobs, move states, or leave the country. You generally should not apply for a new TFN if you’ve lost yours, your original TFN stays valid and can be retrieved.
If you’re running a business or managing a company, having the right tax details on hand helps keep your ATO and ASIC obligations on track.
This guide covers every way to locate it, starting with the fastest. Most people find theirs within five minutes.
If you're setting up a company, your Pty Ltd has its own separate TFN; distinct from your personal TFN, your ABN, and your ACN. Make sure you locate all three before your first BAS lodgement or tax return is due.
Where can you find your TFN in Australia? 4 methods that work
If you need your TFN urgently, work through these four options in order, most people find it within the first two.
1. Check your myGov account
myGov is the fastest way to find your TFN if you already have an account linked to the ATO.
Steps:
- Go to my.gov.au and log in
- Select Australian Taxation Office (ATO), then select Find my TFN
- Your TFN will be displayed on screen
If your myGov account is not yet linked to the ATO, you can link it by selecting ATO from the services menu and verifying your identity using your tax return details or a recent ATO notice.
2. Check ATO correspondence
Your TFN may appear on ATO correspondence and tax records, including your notice of assessment . Check for:
- Notice of Assessment: issued after you lodge a tax return
- Tax return: your TFN appears at the top of lodged returns
- ATO letters: Some ATO letters or notices may include your TFN or enough details to help you identify your tax records.
If you receive ATO communications digitally, check your myGov Inbox for notices or letters.
3. Check previous tax returns
If you have lodged a tax return, either through a tax agent, or directly through myTax, your TFN appears on the return itself.
Check:
- Downloaded PDF copies of previous returns stored on your computer or cloud drive
- Paper copies filed away in your records
- Returns prepared by a tax agent, your agent is required to keep copies and can provide your TFN on request
4. Check payment summaries or income statements
Your TFN appears on:
- PAYG payment summaries from past employers
- Income statements available through ATO online services, which may help you confirm tax records linked to your TFN.
- Superannuation fund correspondence, your super fund holds your TFN on file and correspondence from them may include it
What should you do if you can’t find your TFN?
If you’ve checked all the above and still can’t locate your TFN, your next step is to contact the ATO.
They won’t issue a new TFN, but they will help you retrieve your existing one after verifying your identity.
What to have ready
- Full name and date of birth
- Current and previous address
- Bank account details (for identity checks)
If your identity is confirmed, the ATO will guide you on how to access your TFN.
If you’re working with a tax agent, this can be even faster, they can access it directly through ATO systems.
Most Australians search for their TFN right when they urgently need it. The safest habit is storing it in your ATO Online Services account via myGov; it's always accessible, government-secured, and requires no paperwork.
What should you do if your TFN is stolen or misused?
If your TFN has been exposed, it’s important to act quickly.
A compromised TFN can be used for:
- Identity fraud
- False tax refund claims
- Unauthorised access to government services
What to do immediately
Contact the ATO’s Client Identity Support Centre. They can:
- Place a security flag on your TFN
- Investigate suspicious activity
- Guide you on next steps
Additional actions
- Notify your bank and super fund
- Contact Services Australia if relevant
- Report the issue via cyber.gov.au
- Consider lodging a police report if fraud is involved
And as a rule: never share your TFN unless you’re dealing with a verified and trusted party.
Does a company have a separate TFN in Australia?
Yes, if you have registered a company (Pty Ltd) in Australia, your company has its own TFN that is separate from your personal TFN.
Your company TFN is used to:
- Lodge the company’s annual tax return with the ATO
- Register the company for GST and PAYG withholding.
- Correspond with the ATO on all company tax matters
Where to find your company TFN:
- On the ATO’s letter confirming your company’s tax registration (sent after registration)
- On your company’s annual tax returns
- In your ATO Online Services for Business account
- Through your registered tax agent or accountant
Your company TFN is distinct from your ACN (Australian Company Number, issued by ASIC) and your ABN (Australian Business Number, issued by the ABR). All three are different numbers used for different purposes.
What happens if you don’t have a TFN in Australia?
Not having a TFN can impact you immediately, especially financially.
- Employers may withhold tax at the highest marginal rate of 47%
- Banks may withhold tax on interest
- You may not be able to register for certain tax obligations
- Government payments may be delayed
The good news: any extra tax withheld can usually be claimed back when you lodge your return but it can create unnecessary cash flow pressure in the meantime.
If you use a registered tax agent, you don't need to hunt for your TFN at all, they already have it on file and can provide it to you directly, often faster than calling the ATO yourself.
Need help managing your TFN and ATO obligations?
Finding your TFN is often just the first step. Once you have it, staying on top of your ATO obligations, tax returns, BAS lodgements, GST registration, and payroll, can get complex quickly.
If you’re a business owner or founder, here’s how Sleek makes it easier:
- ATO compliance handled for you
From BAS lodgements and GST registration to PAYG withholding and tax returns, our registered tax agents manage everything accurately and on time, so you’re not chasing deadlines or risking penalties - Complete business setup
Need more than just your TFN sorted? We take care of ABN registration, company incorporation, and full tax setup so you’re compliant from day one - Ongoing accounting support
Whether you’re a sole trader or running a growing company, we support you with tax returns, bookkeeping, and year-round compliance, all with transparent, fixed pricing - ASIC compliance covered
As registered ASIC agents, we handle your annual statements, filings, and company obligations so nothing slips through the cracks
Whether you’re starting out, scaling up, or cleaning up your back-office, Sleek keeps your business compliant, without the stress.
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Frequently Asked Questions
Can my employer find out my TFN?
Your employer holds your TFN on file from the TFN declaration form you completed when you started work, they need it to calculate the correct PAYG withholding. However, employers are legally required to keep your TFN confidential and can only use it for payroll tax purposes.
Can I find my TFN without a myGov account?
Yes. Check your ATO correspondence, previous tax returns, or payment summaries from past employers. If you still can’t locate it, call the ATO with your identity documents and they’ll confirm it over the phone.
What should I do if someone else is using my TFN?
Contact the ATO’s Client Identity Support Centre immediately. They can place a security flag on your TFN to help prevent unauthorised use and will investigate any suspicious or fraudulent activity linked to your number.
