Current and historical annual tables are separated. ACC uses the relevant earnings and published cap; IETC uses eligible whole months and the correct 2025 transition. Student loan payroll estimates are limited to even full-year salary, with assessed amounts available for other cases.

Formula

Income tax = progressive annual table − eligible IETC. Amounts shown = income tax + selected ACC levy + selected student loan repayments. IETC uses income before carried-forward losses and eligible months.

A PRACTICAL GUIDE

When to use this calculator

This calculator can help compare annual income scenarios and understand the separate effects of income tax, ACC and selected student loan repayments. The year ending in March is part of the calculation, so a result for one tax year should not silently be reused for another.

Information to prepare

Prepare annual income, eligible IETC months and the relevant deductions or losses. Review the conditions of each optional component. Income used to test a credit may differ from the amount remaining after losses, and a student loan estimate should not be mistaken for an additional income-tax band.

How to interpret the result

Gross income, taxable income and tax liability are different quantities. A deduction can change the tax base, while a credit or prior payment can change liability or the remaining balance. Under progressive bands, the marginal rate does not necessarily apply to the whole income. An effective rate depends on the denominator used: gross receipts, net income and taxable income can produce different percentages. Read the component labels and included reliefs before treating an effective percentage as a rate for another income scenario.

A practical comparison

Compare the income-tax line first, then add only the levies and repayments relevant to your situation. A monthly equivalent of an annual estimate is not necessarily an employer's exact deduction for an irregular payment. For business invoice prices, use the GST calculator instead of adjusting income-tax rates.

Check your calculation step by step

  1. Match the figures to the selected period and use NZD for monetary inputs. If you start with a document in another currency or covering several periods, resolve that difference before entering a combined amount.
  2. Calculate the documented case first. Then change one input at a time to compare scenarios. Keep the original values available so a change in the result can be traced to a particular assumption rather than several simultaneous edits.
  3. Read the component breakdown alongside the formula and examples below. If an official document differs, check the date, base, rounding and omitted concepts before changing a rate or treating the difference as an error.

Continue with a related calculation

These tools cover other questions in New Zealand. Choose the one that matches the amount you want to check:

If you are comparing countries

Open the relevant jurisdiction when comparing a move, an offer or a transaction abroad. Each tool uses its own currency, period and scope; its result should not be substituted into the current calculation.

Explore all calculators for New Zealand

CHECK THE REFERENCES

Official sources