ABN Lookup
Check any Australian business via the ABR public register. Free, no sign-up.
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What is an ABN and do you need one?
An Australian Business Number (ABN) is an 11-digit number that identifies your business to the government and other businesses. It is issued free by the Australian Business Register (ABR) and is separate from your Tax File Number (TFN), which remains private.
You need an ABN if you are carrying on an enterprise — including freelancing, contracting, running a side business, or operating as a sole trader. Without an ABN, businesses that pay you can legally withhold 47% of your payment (the top tax rate) as a precaution.
An ABN is not just for large businesses. Anyone earning income outside of employment — casual gig work, eBay sales above a threshold, renting out a property — may need one. The test is whether you are conducting an enterprise, not just making occasional sales.
- How to apply: Apply free at abr.gov.au. The process takes about 15 minutes online. You receive your ABN immediately in most cases. You will need your TFN and details of your business structure.
- ABN vs ACN: An ABN identifies your business for tax purposes. An ACN (Australian Company Number) is a 9-digit number issued by ASIC and applies only to registered companies. If you have a company, you have both — the ABN is the ACN with two extra digits added.
- GST registration: Having an ABN does not automatically mean you are registered for GST. GST registration is separate and required once your annual turnover hits $75,000.
- Display requirements: You must include your ABN on invoices, quotes, and receipts. Failure to do so entitles the payer to withhold 47% PAYG tax.
- Keeping it active: If you stop trading, cancel your ABN at abr.gov.au. Holding an unused ABN you are not actively using can cause complications with the ATO.
Frequently asked questions
Yes, completely free. Apply at abr.gov.au — there is no charge. Beware of third-party websites that charge a fee to "apply for an ABN on your behalf." These are unnecessary — the government process is simple and instant in most cases. If someone is charging you $100+ to get an ABN, they are providing no value the ATO does not provide for free.
You can have an ABN if you also run a business or do freelance work alongside your employment. However, you cannot use an ABN to avoid PAYG withholding from your regular employer. Some employers ask contractors to have an ABN, but this does not change whether you are legally an employee or a contractor — the actual working arrangement determines that, and the ATO's employee vs contractor tool can help clarify your status.
An ABN (Australian Business Number) is an 11-digit tax identifier issued by the ATO/ABR for all types of business structures — sole traders, partnerships, trusts, and companies. An ACN (Australian Company Number) is a 9-digit number issued by ASIC specifically for registered companies. Companies have both. If you see an 11-digit number on an invoice, it is an ABN. If you see 9 digits, it is an ACN. A company's ABN is typically its ACN with two digits prepended.
Not automatically — GST registration is a separate step. You must register for GST if your annual turnover reaches $75,000 (or $150,000 for non-profits). Below that threshold, registration is optional. Many businesses register voluntarily to claim GST credits and appear more professional to business clients. Once registered, you must charge GST on taxable supplies and lodge a BAS (Business Activity Statement) — typically quarterly.
Using a false ABN is fraud and can attract significant ATO penalties. The payer has the right — and sometimes obligation — to verify ABN details via the ABR before paying. If an ABN does not match the entity on the invoice, the payer may withhold 47% PAYG tax. This lookup tool can help verify ABNs before paying invoices.