How Bonus Tax Works in New Zealand

If you’ve received a bonus at work, you might have noticed it was taxed heavily. Here’s how bonus tax actually works in New Zealand and why your take-home might be less than you expected.

What IRD Calls a Bonus

In New Zealand, Inland Revenue (IRD) classifies bonuses as “extra pay”. This includes one-off payments like performance bonuses, redundancy payments, back pay, and cashed-up annual leave. Extra pay is taxed differently from your regular salary.

How PAYE is Calculated on Bonuses

Your bonus is not taxed by adding it to your salary and running the whole lot through the normal progressive brackets. IRD treats a bonus as “extra pay” and uses a specific flat-rate method:

1. Work out your annualised regular income (IRD uses your gross earnings for the 4 weeks before the bonus, multiplied by 13 — or your normal annual salary if that’s simpler).
2. Add the bonus to that annualised income to get a “grossed-up” total.
3. Find the single tax-rate band that grossed-up total falls into (using the table below).
4. Apply that one flat rate to the entire bonus — not just the slice of the bonus above the threshold.

This is the key difference from ordinary PAYE: extra pay is not split across brackets the way your normal salary is. Even if your bonus straddles a bracket boundary, IRD applies a single rate to the whole amount, based on where your salary-plus-bonus total lands.

Source: IRD — Calculate PAYE for a lump sum payment. Verified 2026-07-19.

NZ Income Tax Brackets (2025-26) — also used for the extra pay rate table

Example 1 (whole bonus sits in one bracket): You earn $65,000 and receive a $10,000 bonus. Your bonus pushes the grossed-up total to $75,000. Since $75,000 is still within the 30% bracket ($53,501–$78,100), the entire $10,000 bonus is taxed at 30%. Total PAYE on the bonus: $3,000.

Example 2 (bonus straddles a bracket boundary — this is where the flat-rate rule matters): You earn $50,000 and receive a $10,000 bonus. Grossed-up total = $60,000, which falls in the 30% bracket ($53,501–$78,100). Under IRD’s extra pay rule, the whole $10,000 bonus is taxed at 30% = $3,000 — even though $3,500 of that bonus (the slice from $50,000 to $53,500) would have been in the 17.5% bracket if it were ordinary salary. A common mistake is to calculate “tax on salary+bonus minus tax on salary alone” (which would give $2,562.50 here) — that’s the wrong method and understates the PAYE actually withheld.

ACC Earner’s Levy on Bonuses

The ACC earner’s levy of 1.67% also applies to bonus payments, but only up to the annual cap of $152,790 (2025-26). If your salary already exceeds the cap, no ACC levy is deducted from your bonus. If your salary is below the cap but salary plus bonus exceeds it, only the portion below the cap attracts the levy.

KiwiSaver on Bonuses

If you’re enrolled in KiwiSaver, your employee contribution rate (3%, 4%, 6%, 8%, or 10%) applies to bonus payments just as it does to regular pay. Your employer also contributes their minimum 3.5% on the bonus amount.

This is worth considering — while it reduces your immediate take-home, it boosts your retirement savings and you benefit from the employer match.

Student Loan Repayments

If you have a student loan, repayments at 12% apply to the portion of your bonus that, combined with your salary, exceeds the annual repayment threshold of $24,128 (2025-26).

Can You Reduce Tax on a Bonus?

Unlike some countries, NZ doesn’t offer many options to reduce tax on a bonus. However:

• KiwiSaver voluntary contributions — you can make additional voluntary contributions, though these don’t reduce your taxable income
• Donations tax credit — if you donate part of your bonus to a qualifying charity, you can claim a 33.33% tax credit
• Timing — if your employer has flexibility on when the bonus is paid, receiving it in a tax year where your income is lower could reduce the marginal rate

Check Your Bonus Tax

Use our Bonus Tax Calculator to see exactly how much you’ll take home from your next bonus, including PAYE, ACC, KiwiSaver, and student loan deductions.