GST on $500
Both answers, because "GST on $500" means two different things depending on whether that figure already includes GST.
How much GST is on $500?
- If $500 is before GST: GST is $75.00 and the total becomes $575.00.
- If $500 already includes GST: the GST portion is $65.22 and the price before GST is $434.78.
- Working: $500.00 × 1.15 = $575.00 · $500.00 ÷ 23 × 3 = $65.22
$500, worked both ways
| Treating $500 as… | GST | Ex GST | Inc GST |
|---|---|---|---|
| a price before GST | $75.00 | $500.00 | $575.00 |
| a total that includes GST | $65.22 | $434.78 | $500.00 |
| an Australian price at 10% | $50.00 | $500.00 | $550.00 |
The two NZ rows are the ones people mix up. Charging $75.00 of GST on an invoice whose total is meant to be $500 would leave you $9.78 short once Inland Revenue takes its cut — the GST inside $500 is only $65.22.
The two calculations
Adding GST to a GST-exclusive price.
Finding the GST already inside a total.
Stripping GST out to get the ex-GST price.
Taking 15% of a GST-inclusive figure is the common error — it overstates the GST every time. Full guide, with the registration rules and the $60,000 threshold →
Do the next bit too
The number is the easy part. These take it the rest of the way.
Make the invoice
Turn this figure into a compliant GST tax invoice with your logo and download the PDF. The amount carries across automatically.
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See Hnry →GST on other amounts
The rest of the toolkit
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