Your annual salary before tax
Total income from your side hustle
Deductible business expenses
Side Hustle Profit
$10,000.00
Additional Tax
$3,000.00
You Keep
$7,000.00
Marginal Rate
30.0%
Understanding side hustle tax in New Zealand
Side hustle tax in New Zealand
Side hustle income is added to your employment income and taxed at your marginal rate. Since your PAYE job already uses up the lower tax brackets, side hustle income is effectively taxed at your highest marginal rate.
Why does it seem highly taxed?
Your employer withholds PAYE tax as if your job is your only income source. When you add side hustle income, it pushes you higher in the tax brackets. You will likely owe additional tax when you file your IR3 return unless you make voluntary tax payments or pay provisional tax.
Deducting expenses
If your side hustle is a genuine business (not a hobby), you can deduct related expenses such as supplies, equipment, home office, and advertising costs to reduce the taxable profit from your side hustle. You must keep records for at least 7 years.
IRD-Aligned: Uses 2025-26 NZ marginal tax rates. You must declare all side hustle income in your tax return even if tax has not been withheld.
Disclaimer: This calculator provides estimates based on current HMRC rates and thresholds for the 2025/26 tax year. It does not constitute professional tax, financial, or legal advice. Your actual liability may differ depending on your individual circumstances. Always consult a qualified accountant or tax adviser before making financial decisions. Read our terms
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