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Companies

Australian Company Number (ACN)

Key points:

  • When you register a company, ASIC will issue you with a 9-digit Australian Company Number (ACN).
  • The ACN is different to an Australian Business Number (ABN), which is issued by the Australian Taxation Office. Most companies have both.
  • Companies must display their ACN or ABN on some documents.

What an ACN is

An ACN is a unique 9-digit number that identifies a company. ASIC issues every company with an ACN when it is registered.

What an ABN is

An ABN is an 11-digit number used to identify any type of business, including sole traders and partnerships as well as companies.

The ABN is issued by the Australian Taxation Office, not ASIC.

Most companies have an ABN as well as an ACN. A company’s ABN is often the same as the ACN but with 2 extra numbers at the beginning. For example:

  • ACN: 123 456 789
  • ABN: 36 123 456 789.

If this is the case, the company can display its ABN where it would usually have to display its ACN.

Where you must display your ACN

Companies must display their ACN on certain documents. They can use their ABN if it meets the rules above. These documents include:

  • all documents lodged with ASIC
  • invoices and statements of account
  • receipts (unless they are machine-produced)
  • orders for goods and services
  • business letterhead
  • official company notices
  • cheques, promissory notes and bills of exchange.

If a company uses a common seal, it must include the company’s name, the words ‘Australian Company Number’ and the company’s ACN. If the ACN meets the rules above, the seal can use ‘Australian Business Number’, and the company’s ABN instead of the ACN.

How to display your ACN

Your company name and ACN must appear on the first page of all documents where they are required.

If there are multiple companies listed on a document, each company’s ACN must appear next to each company’s name.

Again, if the company’s ABN is the same as the ACN but with two extra numbers at the beginning, the ABN can be shown instead.

The ACN or ABN must be clear and readable, and it must be obvious which company it belongs to.

You may label an ACN as ‘Australian Company Number’, ‘ACN’ or ‘A.C.N.’ You may label an ABN as ‘Australian Business Number’, ‘ABN’ or ‘A.B.N.’

Where you do not need to display your ACN

Companies are not required to display their ACN on items such as:

  • packing and labelling
  • machine-generated receipts such as cash register dockets
  • business cards
  • envelopes
  • vehicles
  • TV advertisements.