Guide
When do you have to register for GST?
Registration is driven by turnover, not profit. Crossing the line changes what you charge, what you can claim, and what your invoices must say.
The decision
Turnover, not profit
The test is GST turnover — your gross business income, not what is left after expenses. A business can be losing money and still be required to register.
The ATO sets the threshold, and different thresholds apply to non-profits and to taxi and ride-sourcing drivers, who must register regardless of turnover. Check ato.gov.au for the current figures before you act.
It is forward-looking as well as backward-looking
You look at the last twelve months and at whether you are likely to reach the threshold in the next twelve. A business that lands one large contract can cross the line on projection alone.
What changes the day you register
| Attribute | Not registered | Registered |
|---|---|---|
| Add GST to sales | No | Yes, 10% |
| Claim GST on purchases | No | Yes |
| Document you issue | Invoice | Tax invoice |
| Lodge a BAS | No | Yes |
That third row catches people out. The invoice maker changes the document heading and removes the GST line when you indicate you are not registered, so you cannot accidentally issue the wrong one.
Registering voluntarily
Below the threshold you may register anyway. It can be worth it when you buy a lot of GST-inclusive inputs and sell mainly to other registered businesses, because you claim the GST back and your customers do not mind the GST you add.
It rarely helps when you sell mostly to consumers. Adding 10% either eats your margin or raises your price.
If you are already over
Registration is generally required within a set period of crossing the threshold, and the ATO can backdate it — which can mean owing GST on sales where you never charged any. Act on it rather than wait.
This is a summary, not advice
Thresholds, timing rules and special cases change. Confirm your own position with the ATO or a registered tax agent before you register or decide not to.
Registration questions
When must an Australian business register for GST?
Once your GST turnover reaches the ATO's registration threshold, or you expect it to within the next twelve months. Turnover means gross income, not profit. Some businesses, such as taxi and ride-sourcing drivers, must register regardless of turnover.
Is the GST threshold based on profit or turnover?
Turnover — your gross business income. A business making a loss can still be required to register.
Can I register for GST voluntarily?
Yes, below the threshold. It tends to help if you buy a lot of GST-inclusive inputs and sell to other registered businesses, and to hurt if you sell mainly to consumers.
What happens to my invoices when I register?
You start charging 10% GST, and your document becomes a tax invoice showing your ABN and the GST amount. Before registration you issue an ordinary invoice with no GST.
What if I should have registered earlier?
The ATO can backdate registration, which may mean owing GST on past sales where you charged none. Speak to a registered tax agent rather than leaving it.