Tax Return / IR3
An IR3 is New Zealand's individual income tax return — an annual declaration of all your income, expenses, and tax credits filed with IRD. However, most employees do not need to file one. If your only income is from salary or wages with correct PAYE deductions, IRD will automatically issue you an income tax assessment after 31 March.
You need to file an IR3 if you earned income not covered by PAYE: self-employment income, rental property income, overseas income, partnership or trust income, or significant untaxed income from other sources. The standard filing deadline is 7 July, or 31 March the following year if you use a registered tax agent.
Even if you're not required to file, it's worth checking your automatic assessment in myIR each year. IRD sometimes misses income sources or credits, and you may be entitled to a refund — or you may owe additional tax that accumulates interest if unpaid.
How it works
IRD's automatic income tax assessment is generated even for many people who never file a return, but that doesn't mean it's always complete — it's worth checking your assessment in myIR each year, since IRD can miss additional income sources or credits you're entitled to, such as the donation tax credit, that only get added if you actively claim them.
The extended 31 March filing deadline exists specifically for taxpayers linked to a registered tax agent, giving nearly a full extra year compared with the standard 7 July deadline for people filing themselves. To use an IR3 well, keep organised records throughout the year — income summaries, expense receipts, rental income records, and any overseas income statements — since IRD's automatic assessment can't account for expenses or income it was never told about.
If you're required to file and don't, IRD can estimate your tax liability from the information it already holds and issue an assessment anyway — this estimate typically won't include deductible expenses you were entitled to claim, and late-filing penalties plus interest can apply on top, so filing late is generally still better than not filing at all.
Frequently asked questions
I only have salary income — do I ever need to file an IR3?
Not usually — IRD automatically assesses salary-and-wage-only income after 31 March, but you should still check the assessment in myIR each year, since it may miss additional income or credits you're entitled to.
What's the real difference between the 7 July deadline and 31 March the following year?
7 July is the standard IR3 deadline if you file yourself; 31 March the following year is an extended deadline available if you're linked to a registered tax agent, giving nearly a full extra year to get your return in.
What happens if I don't file an IR3 when I'm required to?
IRD can estimate your tax based on the information it holds and issue an assessment anyway, which often won't include all your deductible expenses — plus late-filing penalties and interest can apply, so it's usually better to file yourself even if you're late.
Related Terms
IRD
Inland Revenue Department (IRD), commonly known as Inland Revenue or simply IRD, is the New Zealand government agency responsible for collecting taxes, distributing social support payments, and enforcing tax compliance.
PAYE
PAYE (Pay As You Earn) is the system that New Zealand employers use to deduct income tax from employees' wages and salaries.
Provisional Tax
Provisional tax is how self-employed individuals, companies, and others with significant non-PAYE income pay their expected income tax during the year, rather than as a lump sum after year end.