# GST Calculator NZ 2026 — Add or Remove 15%

Source page: https://valem.run/calculators/new-zealand/vat

New Zealand GST is 15%, and it is the only rate. You must register once turnover passes NZ$60,000 in any rolling 12-month period — or once you expect it to in the next 12.

**Tax year:** 2026

## How it is calculated

Inland Revenue states it in its own GST guide: *"GST is a tax, usually 15%, charged by GST registered businesses on the supply (sale) of most goods and services in New Zealand."* There is one rate, so this page asks no category question. The word *usually* carries the exceptions — exports and some financial supplies are zero-rated or exempt — but zero-rating is a different mechanism from a reduced rate, and conflating them changes whether input tax can be claimed.

Because the rate is 15%, the arithmetic has two shortcuts worth knowing. To add GST, multiply by 0.15. To find the GST inside a GST-inclusive price, divide by 7.666… — or, as IR’s own guide puts it, multiply by 3 and divide by 23. A $115 price contains exactly $15 of GST.

The registration test is a **rolling twelve months with a forecast arm**, which is stricter than it first reads. You must register if turnover *was* over NZ$60,000 in the last 12 months **or** is *expected* to go over it in the next 12. So the obligation can arise from a budget rather than an outturn, and it can arise in any month — there is no year end to wait for. Below the figure registration is voluntary, and often still worth it for an exporter, whose zero-rated sales let them reclaim GST on expenses.

## Worked example

With Amount of 100, this model computes Vat Amount of 15.

## Inputs

| Name | Label | Type |
| --- | --- | --- |
| `amount` | Amount | number |
| `direction` | Direction | string |
| `annualTurnover` | Taxable turnover, last 12 months | number |
| `reverseCharge` | B2B reverse charge applies | boolean |

## Sources

- [Inland Revenue - GST guide IR375 (15%)](https://www.ird.govt.nz/-/media/project/ir/home/documents/forms-and-guides/ir300---ir399/ir375/ir375.pdf) (checked 2026-10-05)
- [Inland Revenue - GST guide IR375: registration at NZ$60,000 turnover](https://www.ird.govt.nz/-/media/project/ir/home/documents/forms-and-guides/ir300---ir399/ir375/ir375.pdf) (checked 2026-10-05)

## What this page claims

The Valem engine reproduces this model's formula through 5 self-test cases. That shows internal consistency, not that the formula matches current law; the cited sources are the evidence for that. Estimate, not tax advice.

## For agents

- Model manifest (formula, constants, test vectors): https://valem.run/calculators/new-zealand/vat.json
- Compute by URL: https://valem.run/calculators/new-zealand/vat.json?amount=100
- MCP: https://valem.run/mcp/calculators (call `calculate` with calculator `new-zealand/vat`)