What’s The Difference Between An ABN And ACN?

There can be a lot of confusion between an ACN and ABN number, they are two different business numbers issued by different Australian Government entities. In this article we’ll explore the differences between and ACN and ABN and the different functions that each number serves.


  • An ACN (Australian Company Number) is a 9-digit number issued by the ASIC (Australian Securities and Investments Commission) to all new companies registered in Australia.
  • An ACN is only for a business that registers as a company. Registering a business name is NOT the same as registering a company.
  • Your ACN number must appear on all documents, invoices, statements, letterheads, and advertising material.

Insider Facts

  • Prior to the introduction of an ACN, all company information was filed under a company name. Some company names were up to 80 characters long which caused some serious filing system problems.
  • The introduction of a unique 9-digit number has helped reduce fraud by clearly defining companies and their subsidiaries.


  • An ABN, or Australian Business Number, is a unique 11-digit number issued by the Australian Tax Office to all businesses and associations. This is regardless of their legal structure such as a sole trader, partnership, company and not-for-profits.
  • The advantages of having an ABN is that it can assist with claiming GST credits or claim business expenses such as fuel and stationary.
  • An ABN allows business to easily confirm details in business orders and invoicing.
  • Your ABN helps the government keep track of all your business dealings.
  • If you are self-employed, having and ABN could show lenders that you do indeed own your own business and you’re not simply trying to obtain funds through a low doc loan because of your financial situation.

Insider Facts

Justin Harding