Free tool · New Zealand

GST calculator for New Zealand

Add 15% GST to a price, or work out the GST inside a GST-inclusive total with the 3/23 rule. Shows the working and adds up a list of amounts.

15% GST3/23 ruleAdd up a list

1 · Add or remove GST

GST in New Zealand is 15%.

2 · Add up several amounts

Press Enter or the button to add the amount to a list, e.g. a stack of receipts or the lines of a quote.

Free, no sign-up. Everything is worked out in your browser and your list is saved only on this device. Rounded to the cent per amount. Not tax advice.

How to calculate GST in New Zealand

  • Add GST: price × 1.15. A $400 job becomes $460 with $60 GST.
  • Find the GST in a total: total × 3 ÷ 23. A $460 invoice includes $60 GST.
  • Remove GST: total ÷ 1.15. $460 ÷ 1.15 = $400.

GST is charged at 15% on most taxable supplies, and Inland Revenue uses the 3/23 fraction to find the GST in a GST-inclusive price (Inland Revenue: charging GST).

When you need to register

You must register once your turnover goes over $60,000 in a 12-month period (Inland Revenue: registering for GST). Then you charge GST on your sales, claim it back on business costs and file GST returns.

Other countries: Australia · New Zealand · Canada · India. Need an invoice with the GST on it? Try the free invoice generator.

Quick answers

How do I work out GST in NZ?

To add GST, multiply the price by 1.15: $100 becomes $115. To find the GST in a GST-inclusive price, multiply it by 3 and divide by 23: $115 × 3 ÷ 23 = $15.

What is the 3/23 rule?

GST is 15% of the price before GST, so it makes up 15/115 of the GST-inclusive price, which simplifies to 3/23. Inland Revenue’s example: $100 including GST has $13.04 GST in it.

How do I remove GST from a price?

Divide the GST-inclusive price by 1.15. $115 ÷ 1.15 = $100 before GST.

When do I have to register for GST?

When your turnover was more than $60,000 in the last 12 months, or you expect it to be in the next 12 months. Below that you can choose to register. Check Inland Revenue for your situation.

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