Lost your tax file number? The quickest way to find your TFN is to sign in to myGov and open the ATO service – it is shown in your profile. If you cannot get into myGov, your TFN is printed on your Notice of Assessment, income statement and super statement, your tax agent can give it to you, and the ATO will confirm it over the phone on 13 28 61 after identity checks.
This guide walks through each method in order of speed, what to do if you have never had a TFN, why you must never apply for a second one, and what to do if you think someone else is using yours. Checked against the ATO’s current guidance on 6 October 2026.
Most people have their TFN within a minute of reading this, so start with myGov. The other methods are there for the day your phone is lost or your myGov is locked.
Key takeaways
- Fastest: myGov → ATO → your profile, or the ATO app. Takes under a minute if your myGov is linked.
- On paper: Notice of Assessment, ATO letters and statements of account, income statement or payment summary, super statement.
- By phone: 13 28 61 with identity checks, or ask your registered tax agent.
- You never get a new TFN. One number for life – if you cannot find it you recover it, you do not reapply.
- Stolen or misused TFN: call the ATO Client Identity Support Centre on 1800 467 033 (8 am to 6 pm, Mon-Fri).
Ways to find your TFN at a glance
| Method | How long it takes | What you need |
|---|---|---|
| myGov (ATO linked service) | Under a minute | myGov sign-in with the ATO linked |
| ATO app | Under a minute | Signed in to the app |
| Notice of Assessment or ATO letter | As long as it takes to find the document | Any year’s NOA or a statement of account |
| Income statement / payment summary | As above | From your employer, or in myGov under Employment |
| Super statement | As above | Your fund’s annual member statement |
| Your registered tax agent | One phone call or email | You are their client |
| ATO phone line 13 28 61 | One call, after identity questions | ID details handy; expect waits in July-October |
What is a tax file number?
A TFN is the nine-digit number the ATO uses to identify you across tax, super and some government payments. You keep the same number for life – it does not change when you marry, move interstate or overseas, or switch jobs. You need it to start a job without 47% being withheld, to lodge a tax return, to open an interest-bearing account without top-rate withholding, to apply for government payments, and to combine or check your super.
You are not legally required to have a TFN, but without one you pay more tax than necessary and most financial products are harder to set up. If you are new to Australia, our guide to getting the correct TFN as a new arrival covers the application process.
How do you find your TFN in myGov?
- Sign in to your myGov account.
- Select the Australian Taxation Office from your linked services. If the ATO is not linked yet, follow our guide to linking myGov to the ATO – you will need details from an ATO document or your bank account to link.
- Open My profile (top menu), then Personal details.
- Your TFN is listed with your name, date of birth and contact details.
The ATO app works the same way: sign in and your TFN is in your profile. If you have not set the app up, it needs your myGov sign-in the first time, and you can then use a PIN or face ID.
Which documents show your TFN?
- Notice of Assessment. Every Notice of Assessment you have received shows your TFN. Recent ones are in your myGov inbox; older ones may be in your email or paper files.
- Letters from the ATO, including statements of account and payment reminders.
- Income statement or payment summary from your employer. Current and past income statements are also in myGov under Employment.
- Superannuation statement. Your fund’s annual member statement lists your TFN in the personal details section.
- Payslips sometimes show it, but employers are not required to print it, so do not rely on this.
What if you cannot get into myGov and have no documents?
Two options remain. If you use a registered tax agent, ask them – your TFN is on your file and they can confirm it after their own identity checks. Otherwise, call the ATO on 13 28 61. You will be asked to confirm your identity with personal details and information from your tax records before the number is read out. Lines are busiest in July and August and in the fortnight before 31 October, so call early in the day or outside tax season where you can.
Never apply for a second TFN
People who cannot find their TFN sometimes lodge a fresh application. The ATO does not issue a second number; the application is matched to your existing record and slows everything down, and in the meantime you may have 47% withheld from wages or interest because you quoted nothing. Recover the number using the methods above instead. If you genuinely have never had a TFN, apply through the ATO once, and keep the confirmation letter.
Why does it matter that your employer has your TFN?
You have 28 days from starting a job to give your employer your TFN on a TFN declaration. If you do not, the employer must withhold tax at the top marginal rate plus Medicare levy – 47% – on your pay. The same applies to banks paying interest. The money is credited back when you lodge, but it is a large bite from cash flow for most of a year. If your TFN is on its way from the ATO, tell the employer you have applied and they can withhold at normal rates for the 28 days.
People with a single legal name – common among some arrivals from India and Indonesia – can hit a problem matching their TFN to payroll systems. Our guide to the TFN first-name-only issue explains the fix.
How do you keep your TFN safe?
- Only give it to your employer (via the TFN declaration), your bank or super fund, your registered tax agent, Services Australia and the ATO. Nobody else needs it.
- The ATO will never ask for your TFN by SMS or email, or threaten arrest if you do not pay immediately. Our guide to the four most common tax scams covers the current patterns.
- Do not store it in your phone notes or email it to yourself unencrypted. A photo of your Notice of Assessment in a shared cloud folder is a common leak.
- Check your myGov inbox and ATO account during tax time for lodgements you did not make.
- If you suspect your TFN is compromised, call the ATO Client Identity Support Centre on 1800 467 033, 8:00 am to 6:00 pm Monday to Friday. The ATO can add protections to your record. A compromised TFN is one reason a return gets held for review – see what to do about a potentially compromised TFN.
Rule of thumb
Link myGov to the ATO once and you will never lose your TFN again – it is always one tap away, and so are your income statements, Notices of Assessment and super details. Do it before you need it, not on the morning you start a new job.
FAQ about finding your TFN
How do I find my TFN online?
Sign in to myGov, select the ATO from your linked services and your TFN is shown in your profile details. The ATO app shows it the same way once you have signed in. This is the fastest method and works any time.
Where is my TFN written down?
On your income tax Notice of Assessment, on letters from the ATO such as a statement of account, on your income statement or payment summary from an employer, and on your superannuation account statement. Payslips sometimes show it but are not required to.
Can I find my TFN by phone?
Yes. If you cannot access myGov or any documents, call the ATO on 13 28 61. You will need to answer identity questions before the TFN is given to you. If you use a registered tax agent, you can simply ask them.
Can I get a new TFN if I have lost mine?
No. A TFN is issued once and stays with you for life, even if you change your name, move overseas or stop working. If you have lost it you recover the same number using the methods above. You should not apply for a TFN again.
What if someone else has my TFN?
Tell the ATO as soon as possible. Call the Client Identity Support Centre on 1800 467 033, 8:00 am to 6:00 pm Monday to Friday. The ATO can place extra protection on your account. A compromised TFN is one of the reasons tax returns get held for identity checks.
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Talk to a registered tax agent
If you are a client of Nanak Accountants & Associates, we hold your TFN on file and can confirm it after our identity checks – just call 1300 626 258. If you are not yet a client and want help with your return, a TFN application or dealing with the ATO, book a discovery meeting. Worried about an ATO letter? See how to prepare for a tax audit in Australia.
This article is general information only and is not personal financial or tax advice. ATO methods for finding a lost TFN and the Client Identity Support Centre details were checked against ATO sources on 6 October 2026.
