How to remove GST from a price in Australia
Why you cannot just subtract 10% from a gross price in Australia, and the correct formula for extracting GST.
Key facts
| Place | Australia |
|---|---|
| Tax | GST |
| Standard rate on file | 10% |
| Multiply net price by | 1.1 |
| Tax share of a gross price | 9.09% |
| Currency | AUD |
Why subtracting 10% gives the wrong answer
The tax was calculated on the net price, not on the gross price. Taking 10% off the gross price removes too much. The correct approach is to divide the gross price by 1.1, which returns the net price exactly.
Worked example
Here is the calculation with sample figures. Change any number in the Australia Reverse GST Calculator to run your own.
| Gross amount | A$240.00 |
| Tax rate (%) | 10% |
| Net amount | A$218.18 |
|---|---|
| Tax | A$21.82 |
The tax fraction
If you only need the tax portion, multiply the gross price by 0.0909. That fraction, the rate divided by 100 plus the rate, is sometimes called the tax fraction, and it is useful when you reconcile receipts that only show tax-inclusive totals.
Where this comes up
Expense claims, receipts from shops in Australia, marketplace payouts and quotes given "all in" all need the tax extracted before you can record the net cost correctly in your books.
Quick reference at 10%
Common amounts in Australia, worked both ways: adding tax to a net price, and extracting it from a price that already includes tax.
| Amount | Tax on net amount | Gross (net + tax) | Net if amount includes tax |
|---|---|---|---|
| A$10.00 | A$1.00 | A$11.00 | A$9.09 |
| A$50.00 | A$5.00 | A$55.00 | A$45.45 |
| A$100.00 | A$10.00 | A$110.00 | A$90.91 |
| A$250.00 | A$25.00 | A$275.00 | A$227.27 |
| A$500.00 | A$50.00 | A$550.00 | A$454.55 |
| A$1,000.00 | A$100.00 | A$1,100.00 | A$909.09 |
| A$5,000.00 | A$500.00 | A$5,500.00 | A$4,545.45 |
How Australia compares
Standard rates on file for other countries. A difference of a few points matters most on high-value purchases and on cross-border sales.
| Place | Rate on file | Compared with 10% |
|---|---|---|
| Algeria | 19% | higher |
| Argentina | 21% | higher |
| Armenia | 20% | higher |
| Austria | 20% | higher |
| Azerbaijan | 18% | higher |
| Bahrain | 10% | same |
Using the calculator step by step
- Open the Australia Reverse GST Calculator.
- Type your figures into the numbered lines. Results update as you type.
- Check the rate field. It starts at 10%; change it if a reduced rate, local surcharge or exemption applies to you.
- Read the result on the receipt panel, and use the formula shown under it if you need to explain the figure to a client or colleague.
Key terms
- Taxable income
- Income left after allowances and deductions, on which the tax rates are applied.
- Zero rate
- A rate of 0% on a taxable supply. Unlike an exemption, the seller can usually still reclaim tax on costs.
- Tax credit
- An amount subtracted directly from the tax bill, worth its full face value.
- Standard rate
- The rate that applies to most goods and services unless a specific reduced rate, zero rate or exemption applies.
- Effective rate
- Total tax divided by total income, the average rate you actually pay.
Common mistakes to avoid
- Subtracting 10% from the gross price instead of dividing by 1.1.
- Reclaiming tax on receipts that do not show a valid tax breakdown.
- Recording gross amounts as costs and then reclaiming the tax a second time.
Run your own numbers. The Australia Reverse GST Calculator updates as you type and shows the formula it uses.
Frequently asked questions
How do I remove GST from a price in Australia?
Divide the gross price by 1.1. The difference between the gross and net price is the GST.
What is the GST fraction at 10%?
It is 0.0909 of the gross price.
This article is general information for planning, not tax advice. Rates and rules change; confirm with your tax authority or a qualified adviser.