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Business registration numbers in Australia (ABN, ACN & ARBN): Explained.

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Business registration numbers in Australia (ABN, ACN & ARBN): Explained

This is a comprehensive guide on an ABN, ACN and ARBN in Australia.

Once you have established a company in Australia, you will need to register for a unique number that serves the purposes of identifying your company and is required by law to be displayed on company documents.

Let’s find out more.

Australian company number (ACN)

What is an ACN?

Upon registration of your company, it will be issued with a unique, nine-digit number, known as the Australian Company Number (ACN), used to identify a company and is issued by the Australian Securities Investments Commission (ASIC).

You will automatically receive an ACN once your company is registered.

In the case that the company has changed its name or deregistered, the ACN will remain the same.

Who can get an ACN?

Only companies are eligible for the ACN. Sole traders and partnerships are not entitled to register for an ACN.

Where must the ACN be displayed?

The ACN must appear on the following documents:

  • All documents lodged with the ASIC
  • Business letterheads
  • Cheques, promissory notes and bills of exchange
  • Official company notices
  • Orders for services or goods
  • Receipts that are not machine-produced
  • Statements of account, including invoices
  • Written advertisements making a special offer
  • Common seal (if any)

The ACN is not required to be displayed on the following:

  • Packaging and labelling
  • Advertisements that do not make a special offer
  • Credit cards and credit card vouchers
  • Machine-generated receipts
  • Business cards and with compliments slips
  • Items that are not documents

Australian business number (ABN)

What is an ABN?

An Australian Business Number (ABN) ABN is a unique number used to identify business names and companies and various tax and other business purposes.

Issued by the Australian Business Register (ABR), which is operated by the Australian Tax Office (ATO), an ABN is generally comprised of your ACN with a two-digit prefix.

With an ABN, you can:

  • Confirm your business identity to others when ordering and invoicing
  • Avoid Pay As You Go (PAYG) tax on payments you receive
  • Claim Goods and Services Tax (GST) credits
  • Claim energy grants credits
  • Obtain an Australian domain name

ABN qualifications

The following entities are entitled to register for an ABN:

  • Sole trader
  • Partnership
  • Company
  • Trust

Where must the ABN be displayed?

An ABN must be displayed on the following:

  • Public documents
  • Cheques and negotiable instruments
  • All documents lodged with the ASIC
  • Receipts and invoices
  • Common seal (if any)

According to the ATO, if the ABN is not displayed on an invoice and the total payment for goods and service exceeds AUD 75, the top rate of withholding tax will be withheld from the payment.

Applying for an ABN

The ABR issues the ABN. When applying for an ABN, directors who are Australian residents must provide their tax file number (TFN) for identification purposes.

Non-resident directors must provide certified copies of identification documents. Non-resident shareholders must also provide certified copies of their identification documents (for individuals) or a certified copy of their certificate of incorporation if the shareholder is a corporation.

This process can take several weeks, so being proactive with these documents is essential if time is an issue. These documents are often required for other purposes, such as opening an Australian bank account.

Cancelling the Australian business number

You will need to cancel your ABN in the following situations:

  • Closing your business
  • Changing the business structure
    • Sole trader to a company
    • Sole trader to a partnership
    • Partnership to a company
  • Not operating the business

Australian registered business number (ARBN)

What is an ARBN?

An Australian Registered Body Number (ARBN) is a unique, nine-digit number allocated by ASIC when a body is registered with them other than as a company.

Foreign companies wishing to register with the ASIC will receive an ARBN instead of an ACN.

A body that has been issued with an ARBN can apply for an ABN.

ARNB display rules

Pursuant to the Corporations Act, the ARBN must be displayed on all of the body’s public documents, including negotiable instruments published and signed in Australia.


Eligible businesses and companies must have an ABN, ACN or ARBN in Australia. Along with the company name, these unique numbers are required to be quoted on related company documents, as required by the Corporation Act. If you have any further enquiries, do not hesitate to contact Acclime.

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About Acclime.

Acclime helps established multinational companies and startups start and operate their business in Australia and beyond. By seamlessly navigating our clients through the complexities of the local regulatory systems, we maximise opportunities while ensuring compliance.

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