TFN Guide for Australian Tax Practices

A Tax File Number (TFN) is the Australian Taxation Office’s private identifier for a taxpayer. Before collecting one, identify the person or entity you act for. Then choose an application, recovery or employee declaration according to what the client needs.

What a TFN Identifies

A TFN identifies a taxpayer in Australia’s tax and superannuation systems. TFN stands for Tax File Number. The phrase TFN number means the same thing, although it repeats the word number.

The ATO’s online-services guidance describes a nine-digit TFN. Keep the full number in its protected field. You do not need a realistic sample number to explain it to a client.

An Australian Business Number (ABN) identifies a business or other eligible entity for business dealings. An Australian Company Number (ACN) identifies a registered company. A director ID identifies the director. Each has its own purpose. An ABN or ACN displayed on an invoice does not make the taxpayer’s TFN publicly searchable.

People use a TFN when working, managing super or applying for government payments. Businesses and other entities use one for their tax dealings. myGov’s TFN guidance explains the individual’s uses and distinguishes applying from finding an existing number.

An individual is not committing an offence by declining to quote a TFN. The consequences depend on the payment or service. Higher withholding can apply, and some government payments require a TFN or an accepted exemption. Exemptions are specific to the request. For example, the ATO’s employee rules include some young employees earning below specified amounts.

An exemption for one purpose is not permission to enter an invented number elsewhere. Use the TFN withholding guide for the payment-specific rules.

Having or quoting a TFN does not lodge a tax return. You still assess whether the taxpayer needs to lodge and complete the return where required. Nor does holding a TFN by itself mean every individual must lodge every year.

For Chinese-, Korean-, German-, Indonesian- and Japanese-speaking clients, explain the same Australian identifier. The client’s language does not create a different type of TFN. Ask whether the ATO has already issued an Australian TFN, which taxpayer it belongs to and what the client needs to do with it. A tax identifier from another country does not answer that Australian request.

Use the ATO’s translated tax guidance where available. For help speaking to the ATO, myGov directs clients to the Translating and Interpreting Service on 131 450. The interpreter helps explain the same application or recovery task in the client’s language.

Match the Number to the Client

Collect the TFN belonging to the taxpayer whose affairs you are handling. An individual’s TFN also covers their sole trader business. A company, partnership or trust has its own TFN, separate from the people involved. Government business-registration guidance explains this distinction.

In a fictional example, a director engages your practice for their personal return and the company’s return. The individual record uses the director’s TFN. The company record uses the company’s TFN. Putting the director’s number against the company joins two different taxpayers incorrectly.

For a trust, identify the trust and its trustee separately before requesting information. Collect the trust’s TFN for the trust’s tax affairs. Request a trustee’s personal TFN only where an authorised purpose requires it. Apply the same discipline to a spouse or another director. Their connection to the client does not itself justify collecting their TFN.

When an individual quotes a TFN to a super fund, they quote their existing individual number. They do not apply for a new personal TFN for AustralianSuper, Aware Super or each account. A fund’s own TFN identifies the fund, while a member’s TFN identifies the member.

The OAIC’s lawful-recipient guidance explains why institutions can request TFNs. Banks request them for investment reporting and tax treatment. Super funds use them to identify members’ benefits and administer permitted tax matters. Centrelink requests them to administer relevant payments, as Services Australia’s privacy policy explains.

The client quotes the number to the organisation holding the relevant record. A bank records the TFN against the relevant account. A super fund records it against the member. Centrelink records it for the relevant payment or customer.

Quoting a TFN to one organisation does not recover a lost number or automatically correct every other organisation’s records. Use the TFN details guide when the client’s ATO details also need updating.

Choose Application or Recovery

Apply only when the relevant taxpayer needs a TFN that has not already been issued. A missing copy of an existing TFN calls for recovery. myGov confirms that an individual only needs to apply once.

Client’s situation	Next task	Why it fits
No individual TFN has been issued	Use the individual application guide	The client needs their first individual number.
A company, trust or partnership needs its own number	Use the entity application guide	The entity’s tax record is separate from its people.
A number has been issued but the client cannot find it	Recover the existing TFN	Losing the record does not create a new taxpayer.
The client suspects their TFN has been misused	Follow the compromised-TFN guide and contact the ATO	Protecting the account is a different task from routine recovery.
The client is unsure which entity the number belongs to	Identify the taxpayer and its tax records first	A number copied from another entity can put the wrong taxpayer on the file.

The individual application guide covers the client’s application route. The entity TFN application guide covers entity applications. The ABR confirms that practitioners can apply for those entities through its tax-professional services.

For an issued number, use the TFN recovery guide. If misuse is suspected, use the compromised-TFN guide before treating the problem as a lost record. Keep any number the client recovers out of ordinary email replies.

Keep a Declaration Separate

An employee’s TFN declaration gives the payer information used to work out withholding from payments. It is separate from an application asking the ATO to issue a TFN. Giving an accountant a TFN for a tax return is another request with its own purpose.

A client can already have a TFN and still need to complete a declaration for a new employer. Conversely, filling in a declaration does not itself apply for a first TFN. The employer needs the declaration answers as well as the number, including the relevant residency and tax-free-threshold information.

Use the TFN declaration guide for completing the declaration and the employer’s withholding checks. Keep those payroll instructions with the employer’s task instead of copying the whole form into your client’s onboarding request.

Collect the TFN Without Emailing It

Ask your client to quote their TFN through your practice’s secure collection method, with a notice explaining the authorised purpose. The Tax Practitioners Board’s TFN guidance advises against email collection because email can expose the number.

For an individual’s TFN, the collection notice must explain the authorising law, why you request it and the consequences of declining. It must also say that declining to quote it is not an offence. Collect only information necessary for the authorised purpose. The OAIC’s TFN Rule guidance sets out these requirements.

The Privacy (Tax File Number) Rule 2015 protects individuals’ TFN information. The OAIC explains that it does not cover corporations’, partnerships’, trusts’ or funds’ TFN information. That distinction does not make entity TFNs suitable for public display. Keep the practice’s authorised collection and confidentiality obligations separate from the Rule’s individual scope.

Tax Genie keeps a collected TFN hidden until a staff member reveals it and records every reveal. TFNs stay out of emails, exports and generated documents. Every TFN is removed before AI reviews the client’s answers. You can read how Tax Genie handles TFNs when choosing how to collect them.

Tax Genie checks TFN format as the client types. A format check can identify an entry problem, but it does not prove that the number belongs to the client. Identity checks and authority to act need their own evidence. Tax Genie’s collection checks do not issue a TFN or retrieve one from the ATO. Use the ABN and TFN checking guide for the meaning and limits of these checks.