The Australian business number (ABN) is a unique 11-digit identifier that makes it easier for businesses and all levels of government to interact.

You will need an ABN to:

• Operate in the GST system, including claiming GST credits
• Avoid having amounts withheld from payments to you – your business clients must withhold 46.5% of any payments they make to you if you don’t quote an ABN
• Help other businesses to confirm your business details for ordering and invoicing
• Get an AUSkey to transact online with government agencies
• Be endorsed as a gift deductible recipient or an income tax exempt charity.

Each entity (sole trader, partnership, company or trust) receives one ABN, regardless of the number of commercial activities or enterprises it undertakes. For example, a single entity running a cafe and a newsagency would have only one ABN. But if you set up separate companies, partnerships or trusts, each entity must register in its own right.
If you plan to run your business through a company, you need to register your company and get an Australian company number (ACN) before you can get your ABN.

Put your ABN on your business stationery, especially your invoices. If you don’t, other businesses must withhold 46.5% from any payment they make to you.

To be entitled to an ABN you must be:

• A company registered under corporations law in Australia
• A government entity
• An entity (including an individual) that is carrying on an enterprise in Australia.

Note: A non-resident entity may be entitled to an ABN where either:

• It is carrying on an enterprise in Australia
• In the course of carrying on an enterprise, it makes supplies that are connected with Australia.

Your enterprise does not have to be located in Australia.