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Income Tax · 2026/27

Pro Rata Calculator

Calculate a part-time annual salary from full-time pay and hours.

$

Your calculation

All amounts in New Zealand dollars.

Advanced options KiwiSaver, student loan & tax credit

IETC excludes relevant benefits, NZ Superannuation and qualifying Working for Families circumstances. Check eligibility. One main job, steady pay. No tailored tax codes or other income.

✓ No sign-up needed ✓ Calculated in your browser

A little clarity starts here

Your numbers,
in plain sight.

Enter your details and calculate to see your breakdown.

Using this calculator

Compare a part-time salary fairly

Start with the full-time annual salary and the hours attached to it. Then enter the part-time hours. Compare gross salaries on the same paid-weeks and employment basis.

Worked example

For a $75,000 full-time role at 40 hours, a 24-hour pattern gives $45,000 gross per year: 24 ÷ 40 is 60%.

How the result is built

Full-time salary × part-time hours ÷ full-time hours = pro-rata gross salary. Income tax is then recalculated on that amount rather than reduced by the same percentage.

Before you use the number

Allowances, bonuses and benefit entitlements are not necessarily proportional to hours. Check the agreement instead of assuming every component shrinks at the same rate.

Will net pay also be exactly 60%?

Usually not in this progressive-tax model. The proportion paid in income tax changes when annual income changes, and credit eligibility may change too.

Official source ↗ · How we prepare and correct content · Model reviewed 26 September 2026. Examples are illustrative.

How this tool works

Useful estimates. Clear assumptions.

The 2026/27 year runs from 1 April 2026 to 31 March 2027. We assume a New Zealand tax resident, one main employment, regular earnings and no other income. Figures are annualised estimates, not a payroll filing. Select IETC only after confirming full-year eligibility. Employer KiwiSaver, ESCT, benefits, child support and special deduction rates are excluded.

See calculation rules & official sources ↗
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