Australian Company Number

An Australian Company Number (usually shortened to ACN) is a unique nine-digit number issued by the Australian Securities and Investments Commission (ASIC) to every company registered under the Commonwealth Corporations Act 2001 as an identifier. The number is usually printed in three groups of three digits. It must be quoted on all correspondence and invoices issued by that company. A similar system is used for non-company entities such as trusts, and for foreign companies.

Under the Corporations Act 2001, every company in Australia is issued with a unique, nine-digit number, an Australian Company Number (ACN). Companies are required to disclose their ACN on: the common seal (if any) and every other seal of the company (if any); every public document issued, signed or published by, or on behalf of, the company; every eligible negotiable instrument issued, signed or published by, or on behalf of, the company; and all documents required to be lodged with ASIC.

An ACN is not required on (at least): packaging and labelling, including envelopes and transport documents; advertisements which do not make a specific offer which is capable of being accepted (such as advertisements which only promote the company and its goods or services in general); credit cards and credit card vouchers; machine-generated receipts, including cash-register receipts; business cards and 'with compliments' slips; and items which are not documents (e.g., vehicles, television advertisements).

An ACN remains unchanged even if a company has a name change or is deregistered.

A similar 9 digit Australian Registered Body Number (ARBN) is used for non-company entities such as registerable Australian bodies, and for foreign companies.

When the GST was introduced in Australia the government also introduced a number of complementary measures. These included the ABN, removal of wholesale Sales Tax exemptions and changes to the FBT and changes to the treatment of trusts and charities. A company's Australian Business Number (ABN) frequently includes the ACN as the last nine digits. The ABN indicates that a person, trust or company is registered with the Australian Business Register (ABR). The ABR facilitates and streamlines many Australian business-to-government and government-to-business processes, such as Australian Tax Office transactions involving the collection and remittance of the Goods and Services Tax (GST).

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