If you're a GST-registered business in New Zealand, every invoice you issue needs to meet specific IRD requirements. Get it wrong and your client can't claim their GST back — which creates friction and damages your professional reputation.

This guide walks you through exactly what a valid GST invoice in New Zealand must include, when you're required to charge GST, and how to make the whole process painless.

When Do You Need to Charge GST in New Zealand?

You must register for GST and charge it on your invoices if your annual turnover exceeds NZD $60,000. Once registered, you charge GST at 15% on all taxable supplies.

You can also register voluntarily if your turnover is below $60,000 — many sole traders do this because it lets them claim GST back on business expenses.

What Must a GST Invoice Include?

For a tax invoice to be valid under New Zealand law, it must contain the following:

  • The words "Tax Invoice" prominently displayed
  • Your business name and GST number (your IRD GST registration number)
  • Date of the invoice
  • Description of the goods or services supplied
  • The amount of GST charged (or a statement that GST is included)
  • The total amount payable including GST

For invoices over NZD $1,000, you also need to include:

  • The buyer's name and address (or trading name)
  • The quantity or volume of goods or services supplied

How to Calculate GST at 15%

New Zealand GST is charged at 15%. Here's how the maths works:

Adding GST to a price (exclusive):
Price × 1.15 = Total including GST
Example: $500 × 1.15 = $575 (GST = $75)

Finding the GST in a GST-inclusive price:
Total ÷ 23 × 3 = GST component
Example: $575 ÷ 23 × 3 = $75

Most invoicing software handles this automatically — you enter the amount before GST and the system calculates and displays the GST component and the total.

GST-Exclusive vs GST-Inclusive Pricing

When you quote clients, you can either:

  • Quote GST-exclusive (e.g., "$500 + GST") — common in B2B transactions where the client is also GST-registered
  • Quote GST-inclusive (e.g., "$575 incl. GST") — more common for consumer-facing businesses

Either is fine — just be consistent and make it clear on your invoice which method you're using.

A GST Invoice Example

Here's what a compliant NZ GST invoice looks like:

TAX INVOICE

From: Kiwi Web Design Ltd
GST No: 123-456-789
Date: 9 July 2026

To: Auckland Café Ltd
    123 Queen Street, Auckland

Description: Website redesign — 20 hours @ $100/hr
Subtotal:     $2,000.00
GST (15%):      $300.00
Total:        $2,300.00

Payment due: 9 August 2026
Bank: ANZ | 01-1234-5678900-00

Keeping GST Records

IRD requires you to keep records for at least 7 years. You'll need your invoices when you file your GST return — usually every 2 months (bi-monthly), though some businesses file monthly or every 6 months.

Your GST return reports:

  • GST on sales — what you collected from clients
  • GST on purchases — what you paid to suppliers (your input tax credits)
  • The difference is what you pay to (or claim back from) IRD

Common GST Invoice Mistakes

  1. Missing the words "Tax Invoice" — your client can't claim the GST without this
  2. Wrong GST number — double-check your IRD number matches your GST registration
  3. GST on exempt supplies — some supplies (like financial services and residential rent) are GST-exempt; don't charge GST on these
  4. Not keeping copies — you need a copy of every invoice you issue

How MyBillDash Makes GST Invoicing Easy

MyBillDash is free invoicing software built for New Zealand businesses. You enter your GST number once in your profile, and it appears on every invoice automatically. GST at 15% is calculated for you — just enter your amounts and send.

You get:

  • Professional PDF invoices with all required fields pre-filled
  • Automatic GST calculation at 15% (NZ) or 10% (AU)
  • GST reports for any date range — ready for your IRD return
  • Email delivery direct to your client
  • Free forever plan — no credit card required

Start your free trial and send your first GST invoice in under 5 minutes.