If you carry on a business, you will have an ABN (Australian Business Number). An ACN is also relevant for business but an ABN and an ACN are two different numbers, used for different purposes. In this article, we will explore the differences between and ACN and an ABN and the different functions each serves, and under which circumstances it is appropriate to use one or the other.

What is an ABN?

At its simplest, an ABN is an eleven-digit number which is used for dealings with the Australian Taxation Office. An ABN is issued to all entities, irrespective of how large or small they are.

Under A New Tax System (Australian Busines Number) Act 1999 (Cth), you are entitled to an ABN if you carry on an enterprise in Australia. An ABN is used to make dealings with government and other entities and individuals easier.

What is an ACN?

In contrast, an ACN is a nine-digit number issued by the Australian Securities and Investments Commission (ASIC). It is a unique identifier purely for companies, unlike an ABN which is issued to all entities carrying on a business.

A related query – if you have an ABN, do you have to register for GST?

No, you don’t. It is unnecessary to register for GST if your annual turnover does not exceed $75,000 or if you have a not-for-profit organisation, $150,000.


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Lachlan McKnight

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