Business GST Calculator NZ

Managing GST in Your NZ Business

Every GST-registered business in New Zealand must charge 15% GST on taxable supplies, track the GST on business purchases, and file regular GST returns with Inland Revenue. This calculator helps you work with multiple line items simultaneously, handling the common scenario where some items are quoted exclusive of GST, others are inclusive, and some may be exempt.

GST-Exclusive vs GST-Inclusive Pricing

In New Zealand, businesses are required to display GST-inclusive prices to consumers under the Fair Trading Act. However, business-to-business transactions are commonly quoted GST-exclusive. This creates confusion when preparing invoices that mix both types. This calculator handles both: enter each line item as either exclusive or inclusive, and the totals are calculated correctly across the mix.

GST-Exempt Items

Some supplies are exempt from GST entirely. Financial services (bank fees, insurance premiums, interest), residential rental income, and donations are the most common exempt categories. If your invoice includes exempt items alongside taxable supplies, mark them as "GST Exempt" and the calculator will exclude them from the GST calculation while still including them in the total.

Tax Invoice Requirements

Under section 24 of the Goods and Services Tax Act 1985, a tax invoice must include: your name and GST number, the date, a description of the goods or services, the quantity, the GST-exclusive amount, the GST amount, and the GST-inclusive total. For supplies under $50 (including GST), a simplified tax invoice is acceptable, which only needs to show the supplier's name, date, description, and the GST-inclusive amount. See our GST Invoicing Rules guide for full details.

For the full suite of GST tools, visit the GST.co.nz homepage. For 200+ other NZ calculators, visit Calculate.co.nz.

Last updated: April 2026 | Rates current for the 2026/27 tax year