How to File GST Return in NZ: myIR Guide
File GST return through myIR by reporting total sales/income and total purchases/expenses (both GST-inclusive) for the period. IRD calculates the difference between GST you collected (output tax) and GST you paid (input tax) — you pay the difference, or receive a refund, generally processed within 15 working days.
Table of Contents
What You Need to file GST Return
- Your myIR loginTotal sales and income for the period, GST-inclusive
- Total purchases and expenses for the period, GST-inclusive
- Any adjustments — corrections carried over from a previous period (if you’re not sure what this means, you almost certainly don’t have any)
- Bank account details, if expecting a refund Accounting software (Xero, MYOB, etc.) will generate these totals automatically if you use one — otherwise, calculate manually from your invoices and receipts
Calculate your GST breakdown before you file GST return with our free GST Calculator.
How the GST Return Calculation Works
Your GST return compares two figures:
- Output tax — the GST you collected from customers (from your sales)
- Input tax — the GST you paid on business expenses (from your purchases)
If you collected more than you paid, you pay IRD the difference. If you paid more than you collected — common for exporters and new businesses with high setup costs — IRD refunds you the difference.
Worked example: Ben runs a small IT consultancy. This period he invoiced $34,500 (GST-inclusive). He spent $4,600 (GST-inclusive) on business expenses.
| Item | GST-inclusive amount | GST portion (÷ by 1.15, then × 0.15, or × 3/23) |
|---|---|---|
| Sales invoiced | $34,500 | GST collected: $4,500 |
| Business expenses | $4,600 | GST paid: $600 |
| Net GST to pay IRD | $3,900 |
Step-by-Step GST Filing Process
- Log in to myIR.
- Navigate to your GST account and select the return period due (click “Returns and transactions,” then “File return” next to the period showing the correct end date).
- Choose your filing method — myIR offers two options that lead to the same result:
- “GST amounts” — enter the actual GST figures directly, if you already know them
- “Total sales and purchases” — enter your full GST-inclusive totals and let the system calculate the GST for you
- Enter total sales and income for the period (GST-inclusive).
- Enter total purchases and expenses for the period (GST-inclusive).
- Enter any credit or debit adjustments — corrections from a previous period, only if applicable.
- Review zero-rated supplies separately — these must be recorded, but kept in their own section of the return, distinct from standard-rated sales.
- Review the system-generated assessment — myIR shows a summary confirming whether you owe GST or are due a refund before you submit; check this carefully against your own figures.
- Attach supporting documents if needed — receipts or invoices can be uploaded alongside your return.
- Confirm your bank account if a refund is expected.
- Submit the return.
- Sort your payment, if you owe — pay immediately by direct debit, credit card, or debit card, or arrange to pay later if you need more time before the due date (see our GST Due Dates 2026/27 calendar).
Made a mistake after submitting? Errors can still be corrected even after your return has been filed — contact IRD or amend through myIR rather than worrying it’s locked in permanently.
How Long Does a GST Refund Take?
IRD generally processes GST refunds within 15 working days, unless your return is selected for review — which can extend the timeline while IRD verifies the figures.
What Happens If You File or Pay Late?
Late filing and late payment both trigger penalties and use-of-money interest — see our GST Due Dates guide for the full penalty breakdown. IRD is generally willing to arrange payment plans for businesses that engage proactively before the due date; consistent late filing, however, can eventually trigger more serious consequences, including GST deregistration proceedings.
Do You Need Accounting Software to File?
No — you can file manually through myIR using your own totals. However, software like Xero or MYOB makes the process significantly easier by tracking GST automatically throughout the period, reducing the risk of manual calculation errors, and often integrating directly with myIR for submission.
Frequently Asked Questions
How do I file a GST return in New Zealand?
Through myIR, by entering your total GST-inclusive sales/income and total GST-inclusive purchases/expenses for the period. IRD calculates the difference between GST collected and GST paid.
How long does a GST refund take in NZ?
Generally within 15 working days, unless the return is selected for review, which can extend the timeline.
Do I need Xero or MYOB to file GST?
No, filing manually through myIR is possible. Accounting software just makes tracking and calculating GST easier throughout the period.
What happens if I pay my GST late?
Late payment triggers penalties and use-of-money interest. IRD will often arrange a payment plan if contacted proactively before the due date.
What if I paid more GST than I collected?
You’ll receive a refund from IRD for the difference — common for exporters and new businesses with significant upfront expenses.
Can I fix a mistake after I’ve already submitted my GST return?
Yes. Errors can still be corrected after submission — contact IRD or amend the return through myIR rather than assuming it’s locked in once filed.
What’s the difference between the “GST amounts” and “total sales and purchases” filing methods in myIR?
Both lead to the same result. “GST amounts” is for entering the actual GST figures directly if you already know them; “total sales and purchases” lets you enter your full GST-inclusive totals and has myIR calculate the GST for you.
