The Australian GST System: A Comprehensive Overview
The Goods and Services Tax (GST) is a 10% tax applied to most goods and services sold or consumed in Australia. Introduced in 2000, it transformed the Australian tax landscape, replacing old wholesale sales taxes with a value-added model. While businesses collect GST from their customers, it is the final consumer who ultimately bears the cost.
The $75k Threshold
If your GST turnover is $75,000 or more, registration is mandatory. Ride-sourcing drivers (Uber/Didi) must register from dollar one, regardless of total turnover.
For small businesses, freelancers, and sole traders, GST compliance involves charging 10% on sales, claiming credits on business purchases, and lodging a Business Activity Statement (BAS) — usually every quarter. This tool simplifies that process by providing instant, accurate breakdowns for both single transactions and complex invoices.
Mastering the Math: GST Formulas
Adding GST
To add 10% GST to a net (exclusive) price:
Example: $100 × 1.10 = $110
Extracting GST
To find the GST component of a gross (inclusive) price:
Example: $110 ÷ 11 = $10
The "divide by 11" rule is the secret weapon of Australian accountants. Because 10% is one-eleventh of the final 110% price, it provides the exact tax amount without needing multiple calculation steps.
Taxable vs GST-Free vs Input-Taxed
Taxable Supplies
The standard category. Includes most retail goods, commercial services, and digital downloads. You charge 10% and can claim credits.
GST-Free Supplies
Includes basic food, medical care, education, and exports. You don't charge GST but can still claim credits on your business costs.
Input-Taxed Supplies
Mainly financial services and residential rent. You don't charge GST, but you also cannot claim credits on purchases related to these sales.
2026 BAS Lodgement Deadlines
| Quarter | Period | Due Date |
|---|---|---|
| Quarter 1 | July – September | 28 October |
| Quarter 2 | October – December | 28 February |
| Quarter 3 | January – March | 28 April |
| Quarter 4 | April – June | 28 July |
*Note: Businesses with annual turnover over $20 million must lodge monthly.
GST Reference Table
| Net Price | GST (10%) | Gross Price |
|---|---|---|
| $50.00 | $5.00 | $55.00 |
| $100.00 | $10.00 | $110.00 |
| $250.00 | $25.00 | $275.00 |
| $500.00 | $50.00 | $550.00 |
| $1,000.00 | $100.00 | $1100.00 |
| $2,500.00 | $250.00 | $2750.00 |
| $5,000.00 | $500.00 | $5500.00 |
Expert FAQ: Australian GST
When must I register for GST?
You must register if your GST turnover is $75,000 or more ($150,000 for non-profits). Ride-sourcing drivers must register regardless of turnover. You can also register voluntarily to claim input tax credits.
What is a Tax Invoice?
For taxable supplies over $82.50 (incl. GST), you must issue a valid Tax Invoice. It must include your ABN, the GST amount, and the words "Tax Invoice" clearly.
Is GST charged on delivery?
Generally, yes. Delivery fees follow the GST status of the goods. If the goods are taxable, the delivery is taxable. If the goods are GST-free (like basic food), the delivery may also be GST-free.
How do I claim GST credits?
You can claim back the GST you paid on business purchases if you are registered and hold a valid tax invoice. This is reported as G11 on your BAS.