GST Registration NZ: When Do You Need to Register?

Goods and Services Tax (GST) is one of the first tax obligations most New Zealand business owners encounter — and one of the most commonly misunderstood. Whether you are just starting out or your business is growing fast, understanding when you need to register, and whether it makes sense to register earlier, is important.

Here is a plain-language guide to GST registration in New Zealand.

GST is a 15% tax applied to most goods and services sold in New Zealand. When you are registered for GST, you collect it on behalf of IRD from your customers, and you can claim back the GST you pay on your business expenses.

The key point: GST is not your money. It passes through your business to IRD. Treating it as income is one of the most common and costly mistakes small business owners make.

You must register for GST when your taxable turnover exceeds — or is expected to exceed — $60,000 in any 12-month period.

This threshold applies to your gross revenue, not your profit. If you invoice $60,000 or more in a rolling 12-month window, registration is compulsory.

You have 21 days from the date you exceed the threshold to register with IRD. Miss this and you can be liable for GST on all sales from the date you should have registered — even if you have not collected it from customers.

Yes. You can register for GST at any time, even if your turnover is below the threshold.

Voluntary registration makes sense in several situations:

You have significant business expenses with GST. If you are buying equipment, vehicles, or materials, registering lets you claim back the 15% GST on those purchases. This can be a meaningful cash flow benefit in the early stages of a business.

Your customers are GST-registered businesses. B2B businesses often benefit from registering early because their customers can claim back the GST — so it does not affect the price they pay. You look more established, and you get to claim input tax credits.

You are approaching the threshold quickly. If you are growing fast and expect to hit $60,000 within a few months, registering early avoids the scramble of a forced registration mid-year.

If most of your customers are private individuals (not businesses), adding GST to your prices effectively makes you 15% more expensive than unregistered competitors — unless you absorb the cost yourself.

For service businesses with low expenses and a consumer client base, staying below the threshold and avoiding registration can be a legitimate strategy, at least in the early stages.

Once registered, you need to file GST returns regularly. IRD offers three filing options:

• Two-monthly (most common): File every two months. Good for most small businesses.
• Six-monthly: Available if your turnover is under $500,000. Simpler but means larger payments less frequently.
• Monthly: Available to any business. Useful if you regularly receive GST refunds (e.g. exporters or businesses with high capital expenditure).

Your accountant can advise which period suits your cash flow best.

Invoice basis (most common): You account for GST when you issue or receive an invoice, regardless of when payment is made. This is the default for most businesses.

Payments basis: You account for GST only when cash is actually received or paid. Available to businesses with turnover under $2 million. Better for cash flow if you have slow-paying customers.

IRD takes compulsory registration seriously. If you should have registered but did not:

• IRD can back-date your registration to when you exceeded the threshold
• You will owe GST on all sales from that date — even if you did not collect it
• Penalties and use-of-money interest apply

The practical consequence is that you end up paying GST out of your own pocket on revenue you have already spent. This can be a significant and avoidable problem.

Spending the GST you collect. Set aside 15/115ths of every GST-inclusive payment you receive into a separate account. It is not your money.

Claiming GST on non-deductible expenses. You cannot claim GST on private expenses, even if they are partly business-related. The GST claim must match the business-use percentage.

Missing filing deadlines. GST returns have fixed due dates. Late filing attracts late payment penalties and interest. Set calendar reminders or let your accountant handle it.

Not keeping tax invoices. To claim GST on a purchase over $50, you need a valid tax invoice. No invoice, no claim.

When you register, you need to decide whether your current prices are GST-inclusive or GST-exclusive. This is a business decision with real implications:

• If you add GST on top of existing prices, your customers pay 15% more
• If you absorb GST into existing prices, your effective revenue drops by 13%

For B2B businesses, adding GST on top is usually straightforward. For consumer-facing businesses, the transition needs careful communication.

GST registration is not complicated once you understand the rules — but getting it wrong is expensive. If you are approaching the $60,000 threshold, or if you are wondering whether voluntary registration makes sense for your situation, it is worth a conversation with your accountant before you make the call.

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Eastmure & Associates provides GST advice, registration, and return filing for small businesses, trades, and medical professionals across Christchurch, Canterbury, Selwyn, and Waimakariri.