Australian Business Number
Template:Short description Template:Use Australian English Template:Use dmy dates The Australian Business Number (ABN) is a unique Budget identifier issued by the Australian Business Register (ABR) which is operated by the Australian Taxation Office (ATO). The ABN was introduced on 1 July 2000 by John Howard's Liberal government as part of a major tax reform, which included the introduction of a GST.
The law requires each entity that carries on a business in Australia has an ABN and that the ABN appear on each tax invoice and other tax related documents issued by the entity.
Australian Business Register
The Australian Business Register (ABR) is maintained by the Registrar of the ABR, who is also the Commissioner of Taxation.<ref>Section 28 of the A New Tax System (Australian Business Number) Act 1999 (Cth).</ref> The Registrar registers entities, issuing them with an ABN,<ref>Section 11 of the A New Tax System (Australian Business Number) Act 1999 (Cth).</ref> while the Commissioner of Taxation issues the entity a tax file number.
Entitlement to an ABN
The Registrar issues ABNs only to entities that are entitled to an ABN,<ref>Section 8 of the A New Tax System (Australian Business Number) Act 1999 (Cth).</ref> which can be:
- an individual,
- a body corporate,
- a corporation sole,
- a body politic,
- a partnership,
- any other unincorporated association or body of persons,
- a trust, or
- a superannuation fund.<ref>Subsection 184-1(1) of the A New Tax System (Goods and Services Tax) Act 1999 (Cth).</ref>
For an entity to be entitled to an ABN, it must:
- carry on an enterprise in Australia,<ref>Paragraph 8(1)(a) of the A New Tax System (Australian Business Number) Act 1999 (Cth).</ref> or
- carry on an enterprise that makes supplies connected with Australia,<ref>Paragraph 8(1)(b) of the A New Tax System (Australian Business Number) Act 1999 (Cth).</ref> or
- be a company registered under the Corporations Act 2001 (Cth).<ref>Subsection 8(1) of the A New Tax System (Australian Business Number) Act 1999 (Cth).</ref>
Whether or not an entity is carrying on an enterprise is a question of fact and there are many circumstances where an entity will be carrying on an enterprise. Without being exhaustive, an entity will be carrying on an enterprise if it:
- is in the form of a business,
- leases property,
- is a religious institution,
- is a superannuation fund,
- is an arm of the government, or
- is a charity.<ref>Section 9-20 of the A New Tax System (Goods and Services Tax) Act 1999 (Cth).</ref>
The Registrar can refuse an entity's application to be registered.<ref>Section 13 of the A New Tax System (Australian Business Number) Act 1999 (Cth).</ref> Equally, the Registrar can cancel an entity's registration and thus their ABN.<ref>Section 18 of the A New Tax System (Australian Business Number) Act 1999 (Cth).</ref> Each of these decisions are reviewable taxation decisions.
Applying for an ABN
An entity can apply for an ABN:<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
- online through the Australian Business Register portal,
- using the services of a registered tax agent, or
- lodging a paper-based application with the ATO.
Before applying for an ABN the entity must have a tax file number (TFN).<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
Format
The ABN is an 11-digit number where the first two digits are a checksum. Unlike with the tax file number (TFN), the ATO has publicised the formula for checking and creating valid ABN checksums.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Also, the nature of the ABN algorithm means that any 9-digit number can be made into a valid ABN.
Checksum Method and Verification
The Australian Business Number (ABN) is a unique 11 digit identifier issued to all entities registered in the Australian Business Register (ABR).
The 11 digit ABN is structured as a 9 digit identifier with two leading check digits. The leading check digits are derived using a modulus 89 (remainder after dividing by 89) calculation.
To verify an ABN:
- Subtract 1 from the first (left-most) digit of the ABN to give a new 11 digit number
- Multiply each of the digits in this new number by a "weighting factor" based on its position as shown in the table below
- Sum the resulting 11 products
- Divide the sum total by 89, noting the remainder
- If the remainder is zero the number is a valid ABN
For example, to check if 51 824 753 556 is a valid ABN:
- Subtract 1 from the first (left-most) digit (5) to give 41 824 753 556
- Multiply each of the digits in 41 824 753 556 by the "weighting factor" based on its position as shown in the table below
- Sum (Digit * weight) to give a total of 534
- Divide 534 by 89 giving 6 with zero remainder.
- As the remainder is zero, 51 824 753 556 is a valid ABN.
| Digit | Position | Weighting | Digit * weight |
|---|---|---|---|
| 4 | 1 | 10 | 40 |
| 1 | 2 | 1 | 1 |
| 8 | 3 | 3 | 24 |
| 2 | 4 | 5 | 10 |
| 4 | 5 | 7 | 28 |
| 7 | 6 | 9 | 63 |
| 5 | 7 | 11 | 55 |
| 3 | 8 | 13 | 39 |
| 5 | 9 | 15 | 75 |
| 5 | 10 | 17 | 85 |
| 6 | 11 | 19 | 114 |
| Total: | 534 |