An Australian Business Number (ABN) is a unique 11-digit number that identifies a business or enterprise in its dealings with the government, other businesses and customers. ABNs are issued by the Australian Business Register (ABR), which is run by the ATO, and registering is free.
Who needs an ABN?
You're entitled to an ABN if you carry on a business or enterprise in Australia. Common examples:
- sole traders and freelancers (designers, cleaners, tradespeople, delivery riders);
- contractors paid by invoice rather than as employees;
- partnerships, companies and trusts;
- anyone who needs to register for GST.
Employees don't need an ABN. If an employer asks you to get an ABN for a job that is really employment, ask for advice — you may be missing out on super and other entitlements.
What is it used for?
| Use | Why it matters |
|---|---|
| Invoices | Businesses expect your ABN on invoices. Without it, they may have to withhold 47% of the payment. |
| GST | You need an ABN to register for GST (required from $75,000 annual turnover, or for taxi and ride-sourcing drivers). |
| Business names | You need an ABN to register a business name. |
| Dealing with government | It identifies your business with the ATO and other agencies. |
ABN vs TFN vs ACN
| Issued by | Identifies | Public? | |
|---|---|---|---|
| TFN | ATO | You (or an entity) for tax | No |
| ABN | Australian Business Register | A business or enterprise | Yes |
| ACN | ASIC | A registered company | Yes |
Sole traders usually have a TFN and an ABN. Companies have an ACN, an ABN and their own TFN. More: Is an ABN the same as a TFN? and Understanding ACN numbers.
How to get one
Apply free through the Australian Government's Business Registration Service. See how to get an ABN, how long it takes and how much it costs. Already have one? Find your ABN.