What is the difference between effective and marginal tax rate?

Your marginal tax rate is the rate that applies to your next dollar of income. Your effective tax rate is your total income tax divided by your total income. Because New Zealand uses a progressive tax system, most earners pay an effective rate well below their marginal rate. For example, someone earning $85,000 sits in the 33% bracket, but their effective rate is around 21.1% because the lower portions of their income are taxed at 10.5%, 17.5% and 30%.

Why does the NZ tax system use brackets?

Progressive taxation means lower earners pay a smaller percentage of their income in tax. Every New Zealand earner pays 10.5% on the first $15,600, then 17.5% on income from $15,601 to $53,500, 30% from $53,501 to $78,100, 33% from $78,101 to $180,000, and 39% on anything above $180,000. Only the portion of income that falls within each bracket is taxed at that rate.

Does the ACC levy affect my effective tax rate?

Yes. The ACC earner levy of 1.75% (2026/27) applies to income up to $156,641, adding roughly 1 to 1.75 percentage points to your total effective rate. At $85,000 income the ACC levy adds about $1,488, bringing the combined effective rate from 21.1% to around 22.8%.

Effective Tax Rate Calculator NZ

This calculator shows your effective tax rate on New Zealand income for 2026/27. Most earners are surprised to discover their effective rate is well below the marginal rate they hear quoted. That is because New Zealand uses a progressive system: only the portion of your income that sits in each bracket is taxed at that bracket's rate. Enter your annual income and tick whether to include the ACC earner levy, and the tool works out your total tax, the effective rate, the marginal rate, and gives you a full bracket-by-bracket breakdown so you can see exactly where each dollar of tax comes from.

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Annual income before tax ($)

Include ACC earner levy (1.75% up to $156,641)

Effective tax rate (income tax + ACC)

22.8%

Marginal rate: 33%

Income tax$17,928

ACC earner levy$1,488

Total deductions$19,415

Take-home pay$65,585

Income tax only21.1%effective rate

Tax saving vs
marginal on all$10,123

Your marginal rate is 33% but your effective rate is 21.1% because lower portions of your income are taxed at 10.5%, 17.5% and 30%. Only the income above each threshold is taxed at the higher rate.

2026/27 tax brackets. Estimate only, not financial or tax advice.

Bracket breakdown

Bracket	Tax rate	Income in bracket	Tax paid

How it works

New Zealand's income tax is calculated by applying each rate only to the slice of income that falls within that bracket. The 10.5% rate applies to the first $15,600; 17.5% to income from $15,601 to $53,500; 30% to $53,501 to $78,100; 33% to $78,101 to $180,000; and 39% to anything above $180,000. Add up the tax from each bracket and divide by your total income to get the effective rate.

The ACC earner levy is 1.75% of income up to a maximum liable income of $156,641, giving a maximum levy of $2,741. It is a separate charge from income tax, but it comes out of your pay alongside PAYE, which is why it is useful to see the combined effective rate.

The tax saving versus marginal on all shows how much less tax you pay under the progressive system compared to if your entire income were taxed at your marginal rate. For most earners this is a significant number, and it illustrates why quoting your marginal rate as "your tax rate" overstates what you actually pay.

Worked example

$85,000 annual income, ACC included (2026/27):

First $15,600 at 10.5% = $1,638
$15,601 to $53,500 (i.e. $37,900) at 17.5% = $6,632.50
$53,501 to $78,100 (i.e. $24,600) at 30% = $7,380
$78,101 to $85,000 (i.e. $6,900) at 33% = $2,277
Total income tax: $17,928. Effective income tax rate: 21.1%
ACC levy: $85,000 x 1.75% = $1,488 (rounded)
Total deductions: $19,415. Combined effective rate: 22.8%
Take-home pay: $65,585

The marginal rate is 33% because the income sits in the 33% bracket, but the effective rate is only 22.8% because lower portions were taxed at lower rates.

Marginal vs effective: the common misconception

Many people believe they "pay 33% tax" because they are in the 33% bracket. In reality, only dollars earned above $78,100 attract the 33% rate. All the income below that threshold has already been taxed at 10.5%, 17.5%, and 30%. Your effective rate is the number that matters for understanding how much of your income actually goes to the government.

What this calculator assumes

The 2026/27 NZ income tax brackets: 10.5% to $15,600; 17.5% to $53,500; 30% to $78,100; 33% to $180,000; 39% above.
The ACC earner levy rate of 1.75% (2026/27) up to the maximum liable income of $156,641.
Income entered is your total annual taxable income. It does not deduct KiwiSaver, student loans, Working for Families, IETC or other adjustments.
Results are indicative. Actual deductions depend on your full tax situation.

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