Most New Zealand employees with only PAYE income don’t need to file a tax return — IRD auto-assesses them. But if you have rental income, business income, overseas income, or used the wrong tax code, you need to file an IR3. This step-by-step guide walks you through it.
You must file an IR3 if you earned rental income, business income, overseas income, or received more than $200 in investment income not already taxed. The deadline is 7 July (without a tax agent) or 31 March the following year (with an agent). File online at myir.ird.govt.nz — most IR3s take 20–40 minutes to complete.
Do I Need to File a Tax Return?
You do NOT need to file an IR3 if:
- You only had PAYE employment income from one or two jobs (with correct tax codes)
- IRD has auto-assessed you and you agree with the result
- You have only bank interest that was already taxed at source (RWT)
You MUST file an IR3 if you had:
- Rental property income (from residential or commercial property)
- Self-employment or business income (any amount)
- Overseas income (even if taxed in the overseas country)
- Schedular/contract income over $200 where tax was not withheld
- A student loan and overseas income
- Income from a trust (as a beneficiary)
- You are applying for Working for Families tax credits (use IR3 + IR526)
You SHOULD file if:
- You used the wrong tax code and believe you have overpaid or underpaid
- You have significant deductible expenses not captured through PAYE
- You received a redundancy payment
NZ Tax Year and Deadlines
The NZ income tax year runs from 1 April to 31 March.
| Event | Date |
|---|---|
| Tax year ends | 31 March |
| IRD issues income tax assessments | April – May |
| IR3 due (self-filers) | 7 July |
| IR3 due (with registered tax agent) | 31 March (following year) |
| Tax bill due (standard) | 7 February (following year) |
| Tax bill due (with tax agent) | 7 April (following year) |
| Refunds issued | Typically within 2 weeks of filing |
Step-by-Step: Filing Your IR3 via myIR
Step 1: Set Up myIR
If you don’t already have a myIR account, set one up at myir.ird.govt.nz. You need your IRD number and a RealMe or RealMe verified identity.
Step 2: Gather Your Information
Before you start, collect:
- Income details:
- Employer earnings summaries (available in myIR — pre-populated from payroll data)
- Bank interest statements (your bank provides this or it may be pre-populated)
- Rental income records (total rent received)
- Business income records (total invoices/receipts)
- Overseas income (in NZD, converted at the exchange rate on the date received)
- Deduction records:
- Rental property expenses (rates, insurance, maintenance, mortgage interest)
- Business expenses (check ird.govt.nz for what’s deductible)
- Charitable donations (for a donation tax credit)
- KiwiSaver contributions if you are self-employed
Step 3: Start the IR3 in myIR
Log in to myIR → Income tax → File a return. Select the relevant tax year.
Most data is pre-populated from IRD’s records (employer summaries, interest income, KiwiSaver). Review each section carefully — pre-populated data is not always complete or correct.
Step 4: Complete Each Section
Wages and salary: Confirm the pre-populated figures. If wrong, contact your employer for a corrected employer summary.
Interest income: Pre-populated from bank reporting. Check against your bank statements.
Rental income: Enter total rent received and all deductible expenses. Common rental deductions:
- Mortgage interest (fully deductible from 1 April 2025 for all residential rental properties)
- Rates (council rates)
- Insurance premiums
- Property management fees
- Maintenance and repairs (not capital improvements)
- Depreciation on chattels (not land or building)
Business income: Report total receipts minus allowable expenses. If this is complex, consider using a tax agent or accounting software.
Overseas income: Report all overseas-sourced income. Foreign tax paid may be available as a credit — see IRD’s foreign tax credit rules.
Step 5: Claim Deductions and Credits
Don’t miss these:
- Independent Earner Tax Credit (IETC): If you earned $24,000–$48,000 and didn’t use tax code ME, claim this (worth up to $520)
- Donation tax credits: 33.33% of eligible donations (receipts required)
- Housekeeper credit: If you paid for childcare or home help due to disability (limited circumstances)
- Working for Families: Claim via a separate application (WFF is not on the IR3 itself)
Step 6: Review and Submit
MyIR calculates your tax automatically. Review the outcome:
- Refund: Paid to your nominated bank account, typically within 2 weeks
- Tax to pay: Due by 7 February (or 7 April with a tax agent). You can pay via myIR, internet banking, or by post.
Step 7: Keep Records
Retain all income and expense records for 7 years (IRD may audit up to 7 years in non-fraud cases).
Using a Tax Agent
A registered tax agent (accountant or tax advisor) can:
- File on your behalf with an extended deadline (31 March the following year)
- Review your return for errors and missed deductions
- Represent you if IRD audits or queries your return
For simple returns (single rental property, straightforward self-employment), many agents charge $200–$500. For complex situations, expect more. Check whether the cost is worth it — agents are generally deductible as a business expense for self-employed filers.
Frequently Asked Questions
Do I need to file a tax return as an employee in NZ?
Usually not — if you only had PAYE employment income and correct tax codes, IRD auto-assesses you. Check myIR to see if an assessment has been issued. If you agree with it, no action is needed. Only file an IR3 if you have other income or want to claim deductions not captured in PAYE.
What happens if I miss the IR3 deadline?
IRD charges late filing penalties starting at $50 for returns under $100,000 in tax, plus use-of-money interest on late tax. File as soon as possible — late is better than never. If you cannot pay on time, contact IRD before the due date to arrange a payment plan.
How do I get a NZ tax refund?
Most refunds arise from auto-assessments where you overpaid PAYE. Check myIR in May after year end (31 March) — if you are owed a refund, it will be visible. Click to accept and nominate your bank account. Refunds are typically paid within 1–2 weeks. If you have a tax debt, IRD applies your refund against the debt first.
Can I claim home office expenses on my tax return?
If you are self-employed and work from home, you can claim a proportion of home costs (rent, mortgage interest, rates, power, insurance) based on the proportion of your home used for business. If you are an employee working from home, the rules are more restrictive — you generally cannot claim home office expenses unless your employer requires it and you bear the cost.
What is an income tax assessment and how does it differ from an IR3?
An income tax assessment is IRD’s calculation of your tax based on the information they already hold (PAYE data, bank interest, etc.). It is issued automatically each year through myIR. An IR3 is a self-filed return where you provide the information — required when you have income IRD does not automatically receive.
Worked Example — Rental Property Owner
Scenario: Lisa is a teacher earning $72,000 PAYE. She also owns a rental property that earned $24,000 rent during the year. Her rental expenses were $18,000 (mortgage interest $12,000, rates $2,500, insurance $1,800, property management $1,700).
Net rental income: $24,000 − $18,000 = $6,000
Total taxable income: $72,000 + $6,000 = $78,000
Tax calculation:
- On $14,000 at 10.5% = $1,470
- On $34,000 at 17.5% = $5,950
- On $22,000 at 30% = $6,600
- On $8,000 at 33% = $2,640
- Total PAYE tax: $16,660
Her employer has been withholding PAYE on $72,000 only (~$14,020). At year end she owes the difference — approximately $2,640 in terminal tax plus ACC on the additional income.
Lesson: Rental owners almost always have tax to pay at year end. Set aside 33% of net rental income during the year for provisional tax.
Worked Example — Sole Trader with Employment Income
Scenario: Mike is a graphic designer working part-time at a studio ($35,000 PAYE) and running freelance projects on the side ($22,000 revenue, $8,000 expenses = $14,000 net business income).
Total taxable income: $35,000 + $14,000 = $49,000
Tax calculation:
- On $14,000 at 10.5% = $1,470
- On $34,000 at 17.5% = $5,950
- On $1,000 at 30% = $300
- Total income tax: $7,720
His employer withheld PAYE on $35,000 = approximately $5,225. Terminal tax owed: approximately $2,495.
Mike also pays ACC on his self-employment income at 1.67% on the net business income: $14,000 × 1.67% = $234 additional ACC.
Lesson: Always file an IR3 if you have self-employment income. Set aside 30%+ of your net business income each month in a tax savings account.
What Deductions Can I Claim?
For Rental Property Owners
Since 1 April 2025, mortgage interest is fully deductible on all residential rental properties (the interest limitation rules introduced in 2021 were progressively phased out, with full restoration by April 2025).
| Expense | Deductible? | Notes |
|---|---|---|
| Mortgage interest | ✅ Yes | Fully deductible from 1 April 2025 |
| Council rates | ✅ Yes | |
| Insurance (landlord/building) | ✅ Yes | |
| Property management fees | ✅ Yes | |
| Repairs and maintenance | ✅ Yes | Must be repairs, not improvements |
| Chattel depreciation | ✅ Yes | Carpet, appliances, curtains, etc. |
| Advertising for tenants | ✅ Yes | |
| Accounting fees | ✅ Yes | For preparing rental accounts |
| Body corporate levies | ✅ Yes | For apartment properties |
| Capital improvements | ❌ No | Adding a room, deck — these are capital |
| Building depreciation | ❌ No | Residential buildings not depreciable since 2011 |
| Private use proportion | ❌ No | If property was partially personal use |
For Self-Employed / Sole Traders
| Expense | Deductible? | Notes |
|---|---|---|
| Business equipment | ✅ Yes | Full write-off if under $1,000 each |
| Vehicle (logbook method) | ✅ Yes | % of actual costs based on business use |
| Vehicle (kilometre method) | ✅ Yes | 83c/km for first 14,000km (2025–26 rate) |
| Home office | ✅ Yes | Floor area % × eligible home costs |
| Professional subscriptions | ✅ Yes | Industry body memberships |
| Tools and materials | ✅ Yes | Used for the business |
| Marketing and advertising | ✅ Yes | |
| Subcontractors | ✅ Yes | Amounts paid for outsourced work |
| Meals (client entertaining) | ⚠️ 50% | Only when client is present |
| Meals (own meals working late) | ❌ No | Personal expense |
| Fines and penalties | ❌ No | Traffic fines, IRD penalties |
| Private expenses | ❌ No | Personal purchases, holidays |
Common IR3 Mistakes
1. Not Filing When You Have To
If you have rental or business income and you don’t file, IRD will eventually catch up — through cross-referencing land registry data, bank data, and payment flows. The penalty for non-filing is charged immediately; interest accrues from the due date. Filing late is always better than not filing.
2. Forgetting to Include All Income Sources
All income sources must be declared: NZ employment, overseas income, rental income, business income, interest and dividends, trust distributions, and schedular payments. IRD matches data across multiple systems — omissions are routinely detected.
3. Claiming Private Expenses as Business
Vehicle use, meals, home improvements, and personal purchases are the most common. Always apply the “wholly or partly for business” test. IRD auditors look at expense ratios — if expenses seem high relative to income or industry norms, the return attracts attention.
4. Not Keeping Records
You must keep records for 7 years. Without receipts, you cannot prove deductions. IRD can disallow any expense you cannot support with documentation.
5. Missing the Provisional Tax Obligation
If you owed more than $5,000 in terminal tax in the prior year, you’re required to pay provisional tax the following year (three instalments). Many first-year self-employed people miss this and face a large bill in year two.