Bonus tax calculator NZ
How much of a bonus, back pay or lump sum you keep, under Inland Revenue's extra pay rules.
Why a bonus looks heavily taxed
Your employer adds your last four weeks of pay times 13 to the bonus. That gives an annual figure, and the whole bonus is taxed at the rate for that figure. It is a withholding rate, not your final tax: if too much comes off, your end-of-year tax assessment refunds it.