New Zealand GST calculator: add or remove 15% GST
For one domestic standard-rated supply at 15%. Enter the price before tax or the tax-inclusive total. Not an invoice or a tax return.
Source parameters checked · version 2026-10-16 · review due 2027-01-16
Your inputs (NZD)
Your estimate
This does not determine whether your transaction is taxable.
Methodology and rounding
For an exclusive price, tax = price × 15/100. For an inclusive price, tax = total × 15/115. Round the input to cents, then tax half-up to cents; net and gross reconcile in cents.
Worked example
Price before GST: $1,000.00 · GST (15%): $150.00 · Price including GST: $1,150.00
Assumptions and exclusions
- Does not determine whether a supply is taxable, exempt, zero-rated or outside scope.
- Excludes reverse charge, imports, registration obligations, special schemes, tax recovery and transitional rates.
- Calculates a single amount with half-up cent rounding; item-by-item invoices can round differently.
Questions about this estimate
Does this cover every transaction or product?
No. This tool covers only its stated assumptions. Review the exclusions and official sources before using an estimate.
Are my inputs stored or included in shared links?
No. Calculations and comparisons stay in this tab. The calculator-link action copies the page address without financial inputs. Copy results places the visible figures on your own clipboard.
Official sources and review
Standard rate and inclusive/exclusive arithmetic checked against linked official guidance. This is a limited source check and tested estimate, not professional tax certification.
The calculator stops returning estimates after its review date until its rule version is updated. Report a correction.
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Country guides for this calculator
Read the guide for your market; a general calculator retains its own assumptions.
Explore New Zealand calculators and coverage in NZD. This calculator retains its stated jurisdiction and assumptions.