Add GST to a price, remove GST from a total, or calculate GST on multiple items. Plus a plain-English guide to GST registration and obligations.
GST in Australia is 10% of the GST-exclusive price. The GST-inclusive price is the amount your customer pays. The GST amount is what you collect on behalf of the ATO and report on your BAS.
To find the GST included in a GST-inclusive price, divide by 11. This is because GST is 1/11th of the total price. Use this when you need to find the GST component of a receipt or invoice that already includes GST.
Enter up to 6 line items. Leave the GST field set to "Taxable" for standard goods and services. Set to "GST-Free" for items like fresh food, medical services or eligible NDIS supports.
GST-free items are not zero-rated - they are genuinely exempt from GST. You do not charge GST on GST-free supplies, but you may still be able to claim input tax credits on related purchases. If you are unsure whether a supply is taxable or GST-free, ask us before invoicing.
Key Numbers
Registration
You must register for GST once your annual GST turnover reaches $75,000. The threshold applies to any rolling 12-month period - not just the financial year. That means if you earn $75,000 or more across any consecutive 12 months, you are required to register within 21 days of realising you have crossed the threshold.
A common mistake is checking only the financial year figure. If your business had a strong few months and crossed $75,000 over a rolling 12-month window, you are required to register even if last financial year's total was under the threshold.
You can also register voluntarily if your turnover is below $75,000. This makes sense if your business has significant GST-bearing expenses and you want to claim input tax credits, or if your clients are larger organisations that expect suppliers to be GST-registered.
AffordBooksTax can handle your GST registration and get you set up in Xero correctly from the start. Get in touch if you are approaching the threshold or want to register voluntarily.
Reference
Not all goods and services are treated the same way for GST. Here is a quick reference for common categories.
| Category | GST Treatment | Examples |
|---|---|---|
| Most goods and services | Taxable (10%) | Consulting, trades work, retail sales, restaurant meals, most professional services |
| Basic food | GST-Free | Bread, milk, fresh fruit and vegetables, unprocessed meat. Note: prepared meals, takeaway food and snack foods are taxable. |
| Health services | GST-Free | Medical, dental and many allied health services when provided by a recognised practitioner. Some services may be taxable - check with your accountant. |
| Education | GST-Free | Primary, secondary and tertiary courses. Some vocational training courses. Private tutoring may be taxable. |
| Exports | GST-Free | Goods exported from Australia and some services provided to non-residents. |
| NDIS supports | GST-Free (conditions apply) | Eligible disability supports supplied to NDIS participants with an active plan. Not all NDIS supplies are GST-free. See the NDIS section below. |
| Residential rent | Input Taxed | Long-term residential rental income. You do not charge GST, but you generally cannot claim GST credits on related expenses. |
| Financial supplies | Input Taxed | Most bank fees, loan interest, insurance premiums. Complex area - seek advice if your business provides financial services. |
NDIS Providers
NDIS is one of the most misunderstood areas of GST for small business providers. The general rule is that most NDIS-funded supports are GST-free, but not all of them, and the conditions for GST-free treatment are specific.
For a supply to an NDIS participant to be GST-free, all four of the following must be true:
The ATO specifically flags that treating all supplies as GST-free simply because the client is an NDIS participant is a compliance error seen regularly in BAS lodgements. If a participant's plan lapses, expires or is under review, the GST-free status of your supplies may be affected during that period.
If you provide a mix of taxable and GST-free NDIS supports, your accounting system needs to be set up to distinguish between them correctly. This is something AffordBooksTax helps NDIS providers get right from the start. See our NDIS bookkeeping service for more detail.
Watch Out For
These come up regularly in BAS reviews and ATO audits.
The threshold applies to any rolling 12-month period. If you cross it and do not register within 21 days, the ATO will backdate your registration and you will owe GST on sales you did not collect it on.
To claim a GST credit on a purchase over $82.50, you need a valid tax invoice showing the supplier's ABN and the GST amount. A receipt alone is not enough, and the ATO can disallow the claim.
You can only claim input tax credits on genuine business expenses. Personal costs - groceries, private travel, clothing - cannot be claimed even if paid from a business account.
Not all NDIS supplies qualify as GST-free. If the participant does not have an active plan, or the supply is not in their plan, GST may apply. The ATO flags this as a common BAS error for NDIS providers.
Setting the wrong GST code in Xero means your BAS figures will be wrong. GST-free items should be coded as BAS Excluded or GST-free, not as 10% GST. A bookkeeper can set up your chart of accounts correctly from the start.
Most small businesses lodge BAS quarterly. Missing the deadline attracts a Failure to Lodge penalty and general interest charge on any amount owing. AffordBooksTax clients get the extended agent deadline as standard.
FAQ
Whether you are approaching the registration threshold, setting up for the first time, or unsure about NDIS GST treatment, we can help you get it right from the start.
