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ABN vs ACN [What They Are & How to Get Them]

Written by, Alex Bosnjak

Updated April, 19, 2022

Are you unsure about the difference between ABN vs ACN? In short, both are essential if you want to start a business in Australia. Depending on your business structure, you’ll need one or both.

In this blog post, I’ll break down the differences and similarities between ABN and ACN, who needs them, what information you’ll need, and how to apply for both.

Let’s begin.

What Is an ABN?

An ABN, or Australian Business Number, is an 11-digit number provided by the ATO (Australian Taxation Office). It identifies your business to the government and the public. It’s also your unique identifier when dealing with other businesses.

You need an ABN to:

  • Invoice customers
  • Register for goods and services tax (GST)
  • Apply for business licenses and permits
  • Open a bank account
  • Register for Pay As You Go withholding (PAYG)
  • Participate in tenders for government contracts

What Is an ACN?

ACN is the abbreviation for Australian Company Number. It’s a unique nine-digit number provided by the ASIC (Australian Securities and Investments Commission) to all companies registered in Australia.

ACN is used for:

  • Identifying a company
  • Company registration
  • Taxation purposes
  • Opening a bank account
  • Company documents and correspondence

Are ABN and ACN Necessary?

There’s a lot of confusion about whether or not Australian companies need an Australian Business Number and/or Australian Company Number. So, let’s set the record straight — are ABN and ACN required?

It depends on your specific business circumstances. For example, if you’re running a sole proprietorship, you generally won’t need an ACN, but you must have an ABN. In contrast, you’ll need both if you’re running a company.

In any case, it’s always a good idea to register for an ABN and ACN, even if you’re not legally required to do so. Having both will make your business look more professional. Also, it’ll give you access to benefits and privileges that you wouldn’t get otherwise (like opening a business bank account).

Other OrganisationsYesNo
Sole TradersYesNo

Information Needed for an ABN

You’ll need a few pieces of information to apply for an ABN. Depending on the circumstances, you’ll have to provide some or all of the following information:

  • Proof of being a sole trader, company, or other entity carrying on business in Australia
  • Tax File Number (NTF)
  • Previous ABN, if available
  • ACN or ARBN
  • Business name
  • Business contact information
  • Main business activity

Process of Applying for an ABN

Obtaining an Australian Business Number (ABN) is relatively straightforward. 

You can apply for an ABN online through the Australian Business Register, a government website. The process is as follows:

  1. Once you provide the required information, you’ll be able to select your preferred payment method and submit your application. 
  2. If you provide all the necessary information, you’ll receive your ABN via email.
  3. Right after receiving it, you can apply for other licences.

Information Needed for an ACN

To apply for an ACN, you’ll need to provide:

  • Your company name and contact details
  • Your company’s registered address
  • Information about shareholders
  • Your company’s ABN
  • Details about the company owner

How to Apply for ACN?

You can apply for an ACN online or by mail. The quickest way is to apply online. Another way to register a company in Australia is to hire a private service provider (PSP).

ABN vs ACN: Differences

An ABN is an 11-digit number that identifies your business to the government and the public. You can receive it through the ATO (Australian Taxation Office). 

In contrast, an ACN is a unique nine-digit number assigned by the ASIC (Australian Securities and Investments Commission) when you register your company.

All businesses need an ABN, but not all require an ACN.


An ABN is necessary for all businesses in Australia, while an ACN is only required for companies. Both numbers identify businesses and their owners. They’re required for various purposes, including tax filing and company registration. 

Applying for both numbers is a relatively simple process you can do online or by mail. I hope this article has helped clarify any ACN vs ABN confusion you may have had.


Do I need an ABN or ACN?

You need both an ABN and ACN to run a company in Australia. ABN is required to identify your business to the government and customers, while ACN is necessary to register your company.

Can a company have an ACN without ABN?

No, a company cannot have an ACN without ABN.

Can I have two ABNs?

Yes, you can have two ABNs if you’re a sole trader or company. But you can only have one ACN.

Is the ACN the last nine digits of ABN?

No, the ACN is a unique nine-digit number assigned by ASIC when you register your company. Check my article to get more information on ABN vs ACN and which one you need.