Add New Zealand's 15% GST to a price, or work out how much GST is inside a GST-inclusive amount using the 3/23 fraction.
Tax year Rate in force November 2026Rules checked: November 2026How we calculate
GST included$15.00
Excluding GST
$100.00
Including GST
$115.00
Excluding GST
$100.00
GST 15%
$15.00
Including GST
$115.00
The GST in a GST-inclusive price is 3/23 of the price (not 15%).
This is an estimate based on published rates, not tax or financial advice. Your payslip or assessment may differ. We are an independent site, not affiliated with any government agency.
A tradesperson quoting $2,000 plus GST invoices $2,300, and returns $300 to Inland Revenue in their GST return.
Key facts
GST rate
15% (since 1 October 2010)
Registration threshold
$60,000 turnover in 12 months
GST fraction
3/23
Filing frequency
Monthly, two-monthly or six-monthly
Tips for small businesses
Choose the payments basis if your turnover is under $2 million: you account for GST when money is received or paid rather than when invoiced.
Taxable supply information replaced tax invoices in 2023; for purchases over $1,000 you need the buyer’s details, and for over $200 the supplier’s GST number.
Set aside the GST portion of every sale — it is never your money.
Questions people ask
How do I calculate GST in New Zealand?
To add GST, multiply the GST-exclusive price by 1.15. To find the GST in a GST-inclusive price, multiply it by 3 and divide by 23.
Why 3/23 and not 15%?
Because GST is 15% of the price before GST. A $115 price is $100 plus $15 of GST; $15 is 3/23 of $115.
When do I need to register for GST?
When your turnover is over $60,000 in the last 12 months or is expected to be in the next 12 months. Below that, registration is optional.
Are any goods GST-free?
Exports and some other supplies are zero-rated, and residential rent and most financial services are exempt. Food, including fresh fruit and vegetables, is fully taxed at 15%.
This is an estimate based on published rates, not tax or financial advice. Your payslip or assessment may differ. We are an independent site, not affiliated with any government agency. Read the full disclaimer.
