Extracting 15% GST from a New Zealand price
Why you cannot just subtract 15% from a gross price in New Zealand, and the correct formula for extracting GST.
Key facts
| Place | New Zealand |
|---|---|
| Tax | GST |
| Standard rate on file | 15% |
| Multiply net price by | 1.15 |
| Tax share of a gross price | 13.04% |
| Currency | NZD |
Why subtracting 15% gives the wrong answer
The tax was calculated on the net price, not on the gross price. Taking 15% off the gross price removes too much. The correct approach is to divide the gross price by 1.15, which returns the net price exactly.
Worked example
Here is the calculation with sample figures. Change any number in the New Zealand Reverse GST Calculator to run your own.
| Gross amount | NZ$180.00 |
| Tax rate (%) | 15% |
| Net amount | NZ$156.52 |
|---|---|
| Tax | NZ$23.48 |
The tax fraction
If you only need the tax portion, multiply the gross price by 0.1304. 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 New Zealand, 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 15%
Common amounts in New Zealand, 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 |
|---|---|---|---|
| NZ$10.00 | NZ$1.50 | NZ$11.50 | NZ$8.70 |
| NZ$50.00 | NZ$7.50 | NZ$57.50 | NZ$43.48 |
| NZ$100.00 | NZ$15.00 | NZ$115.00 | NZ$86.96 |
| NZ$250.00 | NZ$37.50 | NZ$287.50 | NZ$217.39 |
| NZ$500.00 | NZ$75.00 | NZ$575.00 | NZ$434.78 |
| NZ$1,000.00 | NZ$150.00 | NZ$1,150.00 | NZ$869.57 |
| NZ$5,000.00 | NZ$750.00 | NZ$5,750.00 | NZ$4,347.83 |
How New Zealand 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 15% |
|---|---|---|
| Morocco | 20% | higher |
| Nepal | 13% | lower |
| Netherlands | 21% | higher |
| Nigeria | 7.5% | lower |
| North Macedonia | 18% | higher |
| Norway | 25% | higher |
Using the calculator step by step
- Open the New Zealand Reverse GST Calculator.
- Type your figures into the numbered lines. Results update as you type.
- Check the rate field. It starts at 15%; 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
- 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.
- Net amount
- The amount before tax is added. On an invoice it is the figure the tax is calculated on.
- Exempt supply
- A sale that falls outside the tax entirely. No tax is charged and input tax usually cannot be reclaimed.
- Withholding
- Tax deducted at source, by an employer or payer, before the money reaches you.
Common mistakes to avoid
- Subtracting 15% from the gross price instead of dividing by 1.15.
- 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 New Zealand 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 New Zealand?
Divide the gross price by 1.15. The difference between the gross and net price is the GST.
What is the GST fraction at 15%?
It is 0.1304 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.