Filing a Tax Return in New Zealand: Assessments, IR3 and Refunds

Automatic income tax assessments: who gets one

You receive an automatic assessment if all your income was taxed before you got it. Inland Revenue lists salary and wages, PIE income such as KiwiSaver, NZ Superannuation, schedular payments to contractors, income-tested benefits like Jobseeker Support, interest, dividends, taxable Māori authority distributions and employee share scheme benefits.

Employers, banks and investment providers send Inland Revenue their figures between 1 April and late May. If you use myIR, expect your assessment between the last weekend in May and the end of July; without myIR it comes later by post, and it can slip to July if a payer is late with its information. Your job is to open the assessment and tell Inland Revenue if anything is wrong or missing. It may ask you for more information before confirming the assessment.

When you must file an IR3 instead

You need an IR3 if you received more than $200 before tax that Inland Revenue has not been told about, even for part of the year. Inland Revenue lists these common reasons. Non-residents file an IR3NR instead.

• Self-employment or "under the table" cash jobs.
• Rental property income, including Airbnb and Bookabach.
• Overseas income.
• Income from an estate, trust or partnership, or as a shareholder or trust beneficiary, and overdue earlier returns.
• Registration for GST or as an employer (IR56 taxpayers and some nanny employers aside), using AIM for provisional tax, or a non-standard balance date.

IR3 due date: 7 July, or later with a tax agent

The IR3 for 2025–26 was due on 7 July 2026 unless you have a tax agent or an extension of time. Filing in myIR is usually processed faster than paper. If you are linked to a tax agent, the agent's extension of time can push the filing date out to 31 March the following year, so 31 March 2027 for 2025–26. When an agent links a new client, the client gets that extension unless more than one return is outstanding.

File late without an extension and the penalty depends on your net income: $50 under $100,000, $250 from $100,000 to $1 million, and $500 over $1 million. Inland Revenue charges $50 first and adjusts it once the return shows your actual income.

Worked example: a refund after working part of the year

Refunds usually mean too much PAYE was taken during the year. PAYE assumes each pay continues all year, so anyone who earns for only part of the year is over-taxed. A worker earning $4,000 a month on code M for 6 months of 2025–26 had $3,653.76 of PAYE deducted. That rate assumes a $48,000 salary.

Her actual income was $24,000. Tax on that is $3,108.00, less $520 independent earner tax credit (she wasn't getting Working for Families, a benefit or NZ Super), so $2,588.00. Her assessment shows a refund of about $1,065.76. The ACC earners' levy is charged per dollar earned, so it doesn't change. The tax refund calculator runs the same comparison for your pay.

Worked example: a tax bill from the independent earner tax credit

Inland Revenue lists the usual causes of a bill: income changing during the year, the wrong tax code or RWT rate, a prescribed investor rate (PIR) set too low, untaxed employee share scheme income, and getting the independent earner tax credit (IETC) when total income ended up over the limit. The last one is easy to miss. Someone earning $64,000 on code ME receives about $520 of IETC through PAYE across 2025–26. In the second half of the year they pick up a weekend job paying $8,000, correctly coded SH, so the second job's own tax is right.

Their total income is now $72,000, above the $70,000 point where the credit stops, so they were entitled to $0. The assessment claws back roughly $520. The fix is a new IR330 for the main job, switching from ME to M as soon as total income looks likely to pass $70,000.

Small bills are often written off. Inland Revenue automatically writes off tax to pay of $50 or less, and some bills caused only by an extra pay period in the year (27 fortnightly pays instead of 26, for example). There is no write-off if you file an IR3, if your income is not yet confirmed, or if your tax code or rate was wrong.

Refunds and tax bills: when the money moves

Inland Revenue pays refunds into the bank account it holds for you when it processes the assessment, so not everyone is paid at once, and the money should arrive within a few days. If a payment bounces, it tries any newer account on file or asks you for one. Part or all of a refund can be used to pay other debt you have with Inland Revenue, including a Working for Families bill for you or your partner; you are told separately when that happens.

Tax to pay is due by 7 February the year after the bill, so 7 February 2027 for a 2025–26 bill. If you have a tax agent with an extension of time, it is due by 7 April. Inland Revenue offers instalment arrangements if you can't pay it all at once. Late payment adds a 1% penalty the day after the due date, a further 4% after seven days, and use-of-money interest at 8.97% on amounts over $100. If your tax to pay is more than $5,000, provisional tax starts the following year.

Before you confirm: a checklist

Spend ten minutes on these before you accept a refund or pay a bill.

• Compare each employer's figures with your final payslip for the year.
• Check the prescribed investor rate (PIR) on KiwiSaver and other PIE funds. A rate that is too low creates tax to pay.
• Add any income Inland Revenue does not know about, such as foreign income, side jobs or cash work.
• Claim donation tax credits separately: one-third of eligible donations over $5, up to your taxable income, in myIR or on the Tax credit claim form (IR526), within four years.
• Check the IETC: if you were paid it through code ME but your total income went over the limit, expect to repay it.