Free New Zealand calculator · 2026/27

Contractor Tax Calculator NZ: IR330C Withholding Tax vs Real Tax

See how much withholding tax (WT) your payer deducts from schedular payments, whether your rate is allowed for your residency, and how WT compares with the income tax and ACC levies you actually owe.

Rules and rates checked against official sources on 2 November 2026 · NZD · Estimates only

How is contractor withholding tax worked out in NZ?

Schedular payments have withholding tax (WT) deducted at the rate on your IR330C: the standard rate for your activity (for example 20% for cleaning or labour-only building), a rate you choose, or 45% if you give no IR330C. The minimum rate you can choose is 10% if you are an NZ tax resident, or 15% if you are a non-resident or hold a temporary entry class visa.

WT is a prepayment, not your final tax. At year end your income tax is worked out on your profit (and any other income) at the normal rates, and WT is credited against it. ACC levies are invoiced separately by ACC — WT does not pay them.

Your details

Your tax residencySets the minimum rate you can elect: 10%, or 15% for non-residents and temporary entry class visa holders.

Which WT rate is on your IR330C?

Schedular payment activity

Your WT rate (%)Elected rates can have one decimal place.

Your income for the year

Schedular payments for the year (NZ$, excl. GST)If you are GST-registered, WT is deducted from the GST-exclusive amount.

Deductible expenses (NZ$)Business costs of earning the contract income.

Salary or wages from a job (NZ$, optional)

Income tax deducted from that job (NZ$, optional)PAYE income tax only, not ACC.

ACC work levy + Working Safer levy ($ per $100)2026/27 averages: $0.69 + $0.08. Check your ACC invoice.

I work more than 30 hours a week on average (ACC minimum liable income can apply)

Your estimate

Withholding tax deducted by your payer—

WT withheld for the year—

Cash received after WT (excl. GST)—

Year-end income tax—

Year-end result (after WT credits)—

ACC levies (not covered by WT)—

WT rate to cover tax / tax + ACC—

Enter your details to calculate.

Withholding tax vs your real tax bill

	What it is	Who collects it
Withholding tax (WT)	Flat % deducted from each schedular payment, excl. GST	Your payer, paid to IRD
Income tax	Progressive tax on your net profit and other income for the year	IRD, through your IR3 return
ACC levies	Earners’ levy (1.75% to $156,641) + work and Working Safer levies	ACC, by invoice after your return

If WT is more than your income tax, IRD refunds the difference. If it is less, you pay the balance — and if that balance (your residual income tax) is over $5,000, provisional tax applies the following year.

Minimum and default WT rates

Your situation	Lowest rate you can elect	If no IR330C
NZ tax resident, not on a temporary visa	10%	45%
NZ tax resident on a temporary entry class visa	15%	45%
Non-resident contractor (individual)	15%	45%
Non-resident contractor company	15%	20%

To go below your minimum you need a tailored tax rate certificate from IRD. Some contractors can get a certificate of exemption (0%), but resident contractors paid by a labour hire business cannot. Non-resident entertainers and sportspeople have a fixed 20% rate and are outside this calculator.

Worked examples

1. Cleaning contractor on the standard 20% rate

Tane is an NZ resident cleaning contractor. He invoices $80,000 (excl. GST) in the year and has $10,000 of expenses.

WT: 20% × $80,000 = $16,000; cash after WT $64,000 (plus GST if registered).
Income tax on $70,000 profit: $13,220.50.
WT credit exceeds the tax, so he gets an estimated $2,779.50 refund.
ACC still invoices him separately: about $1,764 at average 2026/27 levies.
A WT rate of about 16.6% would cover his income tax; about 18.8% would also cover the ACC amount.

2. Electing 15% instead

At 15%, WT is $12,000 and Tane has $1,220.50 income tax to pay at year end, plus ACC.

3. No IR330C

Without an IR330C his payer must deduct 45%: $36,000 on $80,000. The excess comes back only after he files his return.

4. Temporary visa holder

A contractor on a temporary entry class visa who asks for 12% cannot have it: the minimum elected rate is 15%. A lower rate needs a tailored tax rate certificate.

Limits of this estimate

Rates follow the IR330C activity schedule (Schedule 4 of the Income Tax Act 2007). Payments to companies, partnerships and trusts have extra rules and are not modelled.
For non-resident contractors only the withholding is estimated. Their final position depends on residence, any double tax agreement and an IR3NR return.
The year-end figure ignores tax credits (for example the independent earner tax credit), losses and provisional tax payments.
Expenses are not checked for deductibility.

Official sources

Checked 2 November 2026:

Frequently asked questions

What is the minimum withholding tax rate for contractors in NZ?

10% for NZ tax residents, and 15% for non-residents and people on a temporary entry class visa. A lower rate needs a tailored tax rate certificate from Inland Revenue.

What happens if I don’t fill in an IR330C?

Your payer must deduct the no-notification rate of 45% (20% for a non-resident contractor company). You get any excess back after filing your tax return.

Is withholding tax my final tax?

No. WT is a credit against the income tax worked out on your full year’s income in your IR3 return. You may get a refund or have more to pay.

Does withholding tax cover ACC levies?

No. ACC invoices self-employed contractors directly for the earners’, work and Working Safer levies.

Is WT deducted from GST?

No. If you are GST-registered, your payer calculates WT on the GST-exclusive amount.

What rate should I choose?

A rate close to the income tax on your expected profit divided by your contract income. This calculator shows the rate that would roughly cover income tax, and the rate that would also put aside enough for ACC.