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What is an Australian Business number ABN?

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

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

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 sales that are connected with Australia.

Your enterprise does not have to be located in Australia.

You will need to register for an ABN for certain tax purposes, such as GST and pay as you go (PAYG) withholding.

You generally need to quote an ABN on your invoices or other documents relating to sales you make to other business. If you do not quote an ABN when you supply goods or services to another business, they may have to withhold tax from their payment to you at the rate of 47% (from 1 July 2017) under the PAYG withholding system.

When you apply for an ABN you can register for tax obligations such as GST and PAYG withholding at the same time.