GST on invoices in NZ: what has to be on a tax invoice

If you're GST registered in New Zealand, the invoices you send aren't just a request for money — they're a tax document. Inland Revenue calls them "tax invoices," and there's a specific, fairly short list of things they need to contain. Get it right and your client's accounts team pays without asking questions. Get it wrong and you'll be resending the same invoice a week later while the payment sits in limbo.

This is written for any GST-registered small business in NZ — not just sole traders — so it applies whether you're a company, a partnership, or trading under your own name.

First: do you even need a tax invoice?

Only if you're registered for GST. If you're not registered, you don't charge GST and you don't call your document a "tax invoice" — a plain invoice is fine, and it's worth saying so if a client asks why there's no GST line.

As a rule of thumb, you're required to register once your turnover looks like it will pass roughly $60,000 in a 12-month period, though the exact threshold can change over time, so confirm the current figure with your accountant or on the IRD website before deciding either way. Plenty of small businesses register earlier than they have to, because it lets them claim GST back on tools, stock or a vehicle.

The $1,000 rule that trips people up

New Zealand actually has two tiers of tax invoice, and knowing which one applies saves you adding detail you don't need — or leaving out detail you do.

Under $1,000 (including GST): a simplified tax invoice is enough. It needs:

• The words "Tax Invoice" clearly on it.
• Your name (or trading name) and GST number.
• The date of issue.
• A description of the goods or services.
• The total amount payable, including GST.

$1,000 or over (including GST): Inland Revenue expects the fuller version, which adds:

• The client's name and address (or at least enough detail to identify them).
• The quantity or volume of what was supplied.
• Either the GST-exclusive amount, the GST amount, and the GST-inclusive total shown separately — or a statement that the total includes GST along with the applicable rate.

In practice, most invoicing software (including ours) just always shows the fuller breakdown regardless of the amount, because it's clearer for everyone and there's no downside to including more than the minimum. The $1,000 threshold only matters if you're deciding how much detail a bare-bones template needs.

The full checklist, laid out plainly

Whatever the invoice value, a compliant NZ tax invoice needs:

1. "Tax Invoice" written on it, not just "Invoice."
2. A unique, sequential invoice number (INV-0001, INV-0002…) with no gaps and nothing reused.
3. Your legal or trading name and GST number.
4. The client's name (and address for anything at or above $1,000).
5. The date of issue.
6. A description of the goods or services supplied, with quantity where relevant.
7. The GST-exclusive amount, GST amount, and total, shown separately — or the total marked as GST-inclusive with the rate stated.
8. Payment details — bank account number and a reference (usually the invoice number).

Everything after item 8 is optional but helps: a due date instead of "net 14," your logo, and a note about late fees if you charge them.

Rounding and the 15% rate

GST in New Zealand is currently 15%, though rates are set by government and can change, so it's worth a quick check that your invoicing software is using the current rate rather than one you set up years ago. When GST is calculated on a total, round to the nearest cent — most software does this automatically, but if you're building invoices in a spreadsheet, it's a common source of the "your total is one cent out" email from a fussy accounts department.

Buyer-created tax invoices

Occasionally a large client will ask to issue the tax invoice themselves and simply pay you against it — common in construction and some retail supply chains. This is allowed under specific conditions (both parties need to agree to it, usually in writing, and only one party can issue tax invoices for the supply). If a client proposes this, it's worth a quick conversation with your accountant so you know what you're agreeing to and what records you still need to keep on your side.

What if you're not sure a sale is taxable?

Most goods and services supplied in New Zealand are standard-rated at 15%. A smaller set are zero-rated (like exported goods) or exempt (like residential rent and some financial services), and the invoicing rules differ slightly for each. If your business deals in anything outside straightforward local sales — exports, mixed taxable and exempt supplies, or overseas clients — check the specifics with your accountant rather than guessing, since getting the GST treatment wrong is far more annoying to fix after the fact than before you send the invoice.

Record keeping

Inland Revenue expects you to keep copies of tax invoices (issued and received) for seven years. Digital copies are fine — you don't need paper — but they need to be retrievable, not just sitting in a "sent" folder you never look at. This is one of the easiest things good invoicing software solves for you automatically: every invoice is stored, searchable, and exportable the moment it's created, so a seven-year retention rule stops being something you have to think about.

Common mistakes that hold up payment

• Missing GST number. Some clients' accounts systems will bounce an invoice without one.
• "Invoice" instead of "Tax Invoice." A small wording difference that some corporate finance teams treat as a hard requirement.
• GST shown as a lump sum with no rate or breakdown, on an invoice over $1,000 where the fuller detail is expected.
• Reused or skipped invoice numbers — messy for you at GST return time, and occasionally flagged if IRD ever looks closely.
• Charging GST without being registered. If you're not registered, don't add a GST line at all, even "to be safe" — it isn't yours to collect.

Making this automatic

None of this is complicated once, but it's easy to get subtly wrong every time you build an invoice by hand in a spreadsheet — a missing GST number here, a rounding slip there. InvoiceCharlie generates correctly formatted NZ tax invoices automatically once you turn on GST in your settings: the right wording, the right breakdown, sequential numbering, and every invoice stored and exportable for as long as you need it.

If you just need one invoice right now, the free invoice generator will build a GST-ready tax invoice with no account needed. For ongoing invoicing with numbering, reminders and online payment sorted automatically, your first 10 invoices are free — and if you're setting up GST for the first time, our guide on how to invoice as a sole trader in New Zealand covers the registration side in more detail.