How to Set Up a Tax File Number (TFN) for a New Business Entity

Last updated: 29 novembre 2025

A Tax File Number (TFN) is the backbone of your Australian business's tax identity.

Without a TFN, you cannot lodge tax returns, pay staff, or receive ATO correspondence.

Many new shop owners confuse TFN with ABN — they are different. This guide explains exactly when and how to apply for a business TFN, which entity type needs one, and common mistakes to avoid.

1. Business TFN vs. Personal TFN — What's the Difference?

Your personal TFN is for individual tax returns (e.g., your salary, investments). A business TFN is issued to your business entity (sole trader, partnership, company, or trust).

Important: Even if you already have a personal TFN, you still need a separate business TFN if you operate through a company or trust. Sole traders may use their personal TFN for business, but it's cleaner to get a dedicated one.
  • Sole trader: Can use personal TFN, but applying for a sole trader TFN linked to your ABN is recommended.
  • Company (Pty Ltd): Must have a separate company TFN.
  • Partnership or Trust: Must have its own TFN.

2. When Should You Apply for a Business TFN?

You should apply for a business TFN immediately after you receive your Australian Business Number (ABN).

In fact, the ABN application process can auto-create a TFN request. The best practice timeline is:

  • Step 1 — Register your business name with ASIC (if applicable).
  • Step 2 — Apply for an ABN through the Australian Business Register (ABR).
  • Step 3 — During the ABN application, answer 'Yes' to 'Do you need a TFN for this business?' — the ATO will issue one automatically within 28 days.
Pro tip: If you already have an ABN but no TFN, call the ATO Business Line (13 28 66). They can issue a TFN over the phone after verifying your identity.

3. Required Documents and Information

Before you apply, gather the following for each business owner/director/partner:

  • Personal TFN (for each individual associated with the business).
  • Date of birth and residential address.
  • Business address and postal address.
  • Main business activity (e.g., 'Retail – Clothing Shop').
  • Estimated annual turnover.
  • For companies: ACN (Australian Company Number) from ASIC.
  • For trusts: Trust deed details.

4. Step-by-Step Application Process

Online via myGov/ABR (fastest method — 1-2 weeks processing):

  • Log into myGov and link to the ATO.
  • Navigate to 'Register a new business' or 'Update ABN details'.
  • Follow prompts to 'Apply for a TFN'.
  • Submit — you will receive a confirmation receipt. The physical TFN letter arrives by post within 28 days.

Paper application (slow — 6-8 weeks):

  • Download form NAT 4139 (Application for registration of a trust or organisation).
  • Mail to the ATO with certified copies of identity documents.
Warning: The ATO does NOT issue TFNs by email or SMS. If someone offers to 'send your TFN' electronically, it is a scam. TFNs are always physical letters.

5. How to Keep Your Business TFN Secure

Your business TFN is valuable to identity thieves. A criminal with your TFN and ABN could lodge fraudulent BAS claims, steal refunds, and leave you liable.

Follow these rules:

  • Store the TFN letter in a locked safe (not on an open office desk).
  • Never email your TFN to anyone (including your accountant — use a secure portal or encrypted message).
  • Only provide your TFN to trusted parties: your tax agent, payroll software (for STP reporting), and the ATO.
  • If you suspect your business TFN is compromised, call the ATO immediately on 13 28 66 and request a 'new TFN'.

6. What Happens If You Lose Your Business TFN?

If you lose the original letter, do not panic. You can find your business TFN through:

  • Your myGov account (linked to ATO — look under 'Business profiles').
  • Your registered tax agent or BAS agent (they have access to ATO portals).
  • Calling the ATO — they will verify your identity by asking for your ABN, business address, bank account details, and recent BAS amounts.

In summary, setting up a business TFN is straightforward when done alongside your ABN application.

Do not delay — without a TFN, you cannot pay employees, claim deductions, or lodge BAS.

Start this process before your shop opens for trading.

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