Tax return New Zealand: what small businesses and sole traders must file

Published Saturday 15 August 2026

Table of contents

• What is a tax return in New Zealand?
• Who needs to file a tax return in NZ?
• Key tax return dates and deadlines
• NZ income tax rates for the 2026–2027 tax year
• How to file your tax return in New Zealand
• Tax obligations for sole traders and small businesses
• Business expenses you can claim
• Record-keeping requirements
• Common mistakes and how to avoid them
• Simplify your small business tax with Xero
• FAQs on tax returns in NZ

Key takeaways

• Sole traders and small business owners in New Zealand must file an IR3 individual tax return by 7 July each year, or by 31 March the following year if you use a registered tax agent.
• The IR3 covers all your income sources, including self-employment, rental, and investment income, and lets you claim eligible business expenses to reduce your taxable income.
• Provisional tax applies if your residual income tax from the previous year exceeded $5,000, requiring you to pay tax in instalments throughout the year.
• GST registration is compulsory once your business turnover passes $60,000 in any 12-month period, and ACC levies apply to all self-employed earners in New Zealand.

What is a tax return in New Zealand?

A tax return is a form you file with Inland Revenue (IR) to report all the income you've earned during a tax year and calculate how much tax you owe or are owed back. In New Zealand, the tax year runs from 1 April to 31 March.

For sole traders and small business owners, the relevant form is the IR3 individual tax return. You use it to declare income from all sources, claim deductions for business expenses, and work out your final tax position for the year.

Many salary and wage earners in New Zealand receive an automatic assessment from Inland Revenue at the end of each tax year. This is sometimes called a personal tax summary, and it's generated automatically using information from employers and banks.

If you earn income that isn't taxed at source, such as self-employment income, rental income, or certain types of investment income, you'll need to file an IR3 instead of relying on an automatic assessment. The IR3 gives you the opportunity to declare all your income, claim deductions, and make sure you've paid the right amount of tax.

Who needs to file a tax return in NZ?

Not everyone in New Zealand needs to file a tax return manually. If you only earn salary or wages with tax deducted through PAYE, Inland Revenue will generally handle your assessment automatically. But several situations require you to file an IR3.

Sole traders and self-employed

If you're a sole trader or self-employed, you must file an IR3 every year. This applies whether your business is your main source of income or a side activity alongside regular employment.

As a sole trader, your business income is treated as your personal income. You're responsible for reporting it to Inland Revenue and paying the correct amount of tax. You'll also need to keep records of your income and expenses throughout the year to complete your return accurately. For more on how to register as a sole trader, check out this helpful guide.

Rental income earners

If you earn rental income from property, you need to file an IR3. This includes income from long-term tenancies, short-term holiday rentals, and boarding arrangements.

You can claim expenses related to your rental property, such as mortgage interest, rates, insurance, and maintenance costs. These deductions can reduce the amount of tax you pay on your rental income.

Other situations requiring an IR3

Beyond self-employment and rental income, you'll need to file an IR3 if you receive any of the following types of income:

• Overseas income from employment, investments, or pensions
• Trust income where tax hasn't been fully deducted
• Partnership or look-through company income
• Investment income over $200 that hasn't had resident withholding tax (RWT) deducted at the correct rate
• Shareholder-employee salary where you need to square up your tax at the end of the year
• Income from the sale of property that's subject to the bright-line test

Key tax return dates and deadlines

Staying on top of your tax deadlines helps you avoid late-filing penalties and use-of-money interest charges. Here are the key dates for the 2025–2026 tax year:

• Tax year: 1 April 2026 to 31 March 2027
• IR3 filing deadline: 7 July 2027
• IR3 filing deadline with a tax agent extension: 31 March 2028
• Terminal tax payment due: 7 February 2028
• Terminal tax payment due with a tax agent extension: 7 April 2028

If you're required to pay provisional tax, your instalment dates depend on the method you use. Under the standard method, provisional tax is typically paid in three instalments throughout the year: on 28 August 2026, 15 January 2027, and 7 May 2027. Your tax agent can confirm the exact dates based on your circumstances.

Filing through a registered tax agent gives you more time to prepare your return and pay any tax owed. If you haven't used a tax agent before, consider engaging one well before your filing deadline.

NZ income tax rates for the 2026–2027 tax year

New Zealand uses a progressive tax system, which means different portions of your income are taxed at different rates. You pay the lower rate only on the income that falls within that bracket, not on your entire income. Here are the income tax brackets from 1 April 2026:

• $0 to $15,600: taxed at 10.5%
• $15,601 to $53,500: taxed at 17.5%
• $53,501 to $78,100: taxed at 30%
• $78,101 to $180,000: taxed at 33%
• $180,001 and above: taxed at 39%

For example, if your taxable income is $60,000, you don't pay 30% on the full amount. Instead, you pay 10.5% on the first $15,600, then 17.5% on the next $37,900 (up to $53,500), and 30% on the remaining $6,500.

Unlike some other countries, New Zealand has no tax-free threshold. You pay tax from the first dollar you earn. If your annual income falls between $24,000 and $48,000, you may be eligible for the independent earner tax credit (IETC), which provides a credit of up to $520 per year to help reduce your tax bill.

How to file your tax return in New Zealand

Filing your IR3 tax return is a straightforward process once you have your records in order. Here's what to expect at each stage.

What you need before you start

Before you begin your IR3, gather the following information:

• Your total business income for the tax year, including invoices and sales records
• A summary of all your business expenses, with receipts and supporting documents
• Details of any other income, such as rental, investment, or overseas income
• Your IRD number and bank account details for any refund
• Records of any tax already paid, including provisional tax instalments and RWT certificates

Filing through myIR step by step

Most sole traders and small business owners in New Zealand file their IR3 online through Inland Revenue's myIR portal. Here's how to do it:

1. Log in to your myIR account at ird.govt.nz. If you don't have a myIR account, you'll need to register first.
2. Select "Returns and transactions" from the main menu, then choose the IR3 return for the relevant tax year.
3. Work through each section of the return, entering your income from all sources.
4. Enter your business expenses and any other deductions you're entitled to claim.
5. Review the calculated tax amount and check it against any tax you've already paid during the year.
6. Submit the return and note any tax to pay or refund due.

After you submit, Inland Revenue will process your return and confirm whether you have tax to pay or a refund coming. Refunds are typically processed within one to two weeks.

Filing with a tax agent

If your tax situation is complex, or you'd prefer professional support, you can engage a registered tax agent to file your IR3 on your behalf. A tax agent can help you identify deductions you might have missed and make sure your return is accurate.

Using a tax agent also extends your filing deadline from 7 July to 31 March the following year, giving you extra time to get your records together. Your payment deadline also extends to 7 April.

Tax obligations for sole traders and small businesses

Beyond filing your annual IR3, there are several ongoing tax obligations you need to manage as a sole trader or small business owner.

GST registration and filing

Goods and services tax (GST) is a 15% tax on most goods and services sold in New Zealand. You must register for GST if your business turnover exceeds, or is expected to exceed, $60,000 in any 12-month period.

Once registered, you'll need to file regular GST returns (monthly, two-monthly, or six-monthly) and pay the GST you've collected to Inland Revenue. You can also claim back GST on your business purchases.

If your turnover is below $60,000, you can choose to register voluntarily. Voluntary registration can be beneficial if your business makes significant purchases, as it allows you to claim back the GST on those costs. It also means you'll need to charge GST on your sales and file regular returns, which adds to your admin.

ACC levies

All self-employed people in New Zealand are required to pay Accident Compensation Corporation (ACC) levies. These levies fund the cost of personal injury cover for everyone in the country.

As a self-employed earner, you'll pay three types of ACC levy:

• Earners' levy: covers non-work injuries and is currently 1.75% of your liable earnings
• Work levy: covers work-related injuries and varies depending on your industry and the level of risk involved
• Working safer levy: a small flat-rate levy that funds workplace health and safety initiatives

Inland Revenue collects your ACC levies as part of your income tax assessment. You don't need to register separately with ACC, but you do need to make sure your income is reported correctly so the right levy amounts are calculated.

Provisional tax

Provisional tax is a way of paying your income tax in instalments throughout the year, rather than in one lump sum at the end. You're required to pay provisional tax if your residual income tax was more than $5,000 in the previous tax year.

There are four methods for calculating provisional tax:

• Standard method: based on your previous year's tax, with an uplift applied
• Estimation method: you estimate your current year's income and pay tax based on that estimate
• Ratio method: available if you're GST-registered, this method calculates provisional tax as a percentage of your GST-period sales
• Accounting income method (AIM): uses your accounting software to calculate provisional tax based on your actual year-to-date income each period

Each method has different payment dates and requirements. If you're unsure which method suits your situation, talk to your tax agent or accountant.

Business expenses you can claim

One of the key benefits of filing an IR3 is the ability to claim deductions for legitimate business expenses. Claiming your expenses reduces your taxable income, which means you pay less tax.

To be deductible, an expense must be directly related to earning your business income. Common business expenses for sole traders and small businesses in New Zealand include:

• Home office costs: if you work from home, you can claim a portion of your rent or mortgage interest, power, internet, and phone expenses based on the area of your home used for business
• Vehicle expenses: you can claim the business use of your vehicle, either by keeping a logbook or using Inland Revenue's kilometre rate
• Equipment and tools: computers, phones, software, and other equipment used for your business
• Professional fees: accountant, tax agent, and legal fees related to your business
• Insurance: business-related insurance premiums, such as public liability and professional indemnity
• Business travel: flights, accommodation, and meals for business-related travel away from your usual place of work

Keep detailed records and receipts for every expense you claim. Inland Revenue may ask you to provide evidence to support your deductions.

Record-keeping requirements

Good record keeping is a legal requirement for all businesses in New Zealand. Inland Revenue requires you to keep records for at least seven years from the end of the tax year they relate to.

Your records should include the following:

• All income received, including invoices, sales records, and bank statements
• All business expenses, with receipts, invoices, and proof of payment
• Asset purchase and disposal records
• GST records, if you're registered
• Bank statements for all business accounts

Organising your records throughout the year makes tax time significantly easier. Rather than gathering everything at the end of the financial year, set aside time each week or month to update your records.

A few tips for keeping your records in order:

• Use a separate bank account for your business transactions to keep personal and business finances apart.
• Save digital copies of receipts as backups in case paper copies fade or get lost.
• Reconcile your bank transactions regularly so your records stay up-to-date.
• Use cloud-based accounting software to automate data entry and store records securely.

Common mistakes and how to avoid them

Even experienced business owners can make errors when filing their tax return. Here are some of the most common mistakes and how to steer clear of them.

• Missing filing deadlines: Set calendar reminders well ahead of the 7 July deadline, or engage a tax agent early to take advantage of the extended deadline.
• Forgetting to declare all income: Your IR3 must include income from every source, not just your main business. Check for bank interest, rental income, overseas income, and any one-off payments you may have received.
• Not claiming all eligible expenses: Review your records carefully to make sure you haven't overlooked deductible expenses. Small costs like software subscriptions, professional memberships, and home office expenses can add up.
• Mixing personal and business finances: Use a dedicated business bank account to keep your finances separate. This makes it easier to track income and expenses, and reduces the risk of errors in your return.
• Ignoring provisional tax obligations: If your tax bill exceeded $5,000 last year, you're likely required to pay provisional tax. Failing to make your instalment payments on time can result in use-of-money interest and penalties.
• Underestimating penalties: Late filing and late payment penalties can add up quickly. Inland Revenue charges an initial late-payment penalty of 1% the day after the due date, followed by a further 4% penalty on the seventh day. An additional 1% penalty is then added each month the tax remains unpaid.

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FAQs on tax returns in NZ

Here are answers to some common questions about filing tax returns in New Zealand.

How long does it take to get a tax refund in NZ?

If you file your IR3 online through myIR, refunds are typically processed within one to two weeks. Processing times may be longer if Inland Revenue needs to review your return or request additional information.

Can I file my tax return myself without an accountant?

Yes, you can file your IR3 yourself through Inland Revenue's myIR portal at no cost. If your income comes from multiple sources or you're unsure about what you can claim, a tax agent can help you get it right.

What happens if I miss the tax return deadline?

Inland Revenue may charge a late-filing penalty and use-of-money interest on any tax that remains unpaid after the payment due date. Contact Inland Revenue as soon as possible if you think you'll miss a deadline.

Do I need to file a tax return if I only earn PAYE income?

In most cases, no. If your only income is from salary or wages with tax deducted through PAYE, Inland Revenue will issue an automatic assessment at the end of the tax year. You'll only need to file an IR3 if you have additional income or if your tax hasn't been deducted at the correct rate.

What is the difference between an IR3 and an automatic assessment?

An automatic assessment is generated by Inland Revenue using information already held from employers and banks. An IR3 is a tax return you file yourself to declare income that isn't covered by automatic assessment, such as self-employment or rental income. The IR3 also allows you to claim deductions for business expenses.