NZ Tax Deadlines 2026–2027: Every Key Date in One Simple Guide
- Haley Reyners
- 3 hours ago
- 4 min read
Staying on top of tax deadlines shouldn’t feel harder than running your business.
This guide gives you a clear, practical reference for the key GST and Income Tax dates from 1 April 2026 to 31 March 2027, so you can check what’s coming up at a glance and stay one step ahead of the deadlines.
Quick Navigation
Income Tax Due Dates (2026–2027)
These are the key income tax dates most business owners need to know for a standard 31 March balance date.
Date | What’s due |
7 April 2026 | Terminal tax (with tax agent extension) |
7 May 2026 | Provisional tax instalment |
7 July 2026 | 7 July 2026 Income tax return (no tax agent) |
28 August 2026 | Provisional tax instalment |
15 January 2027 | Provisional tax instalment |
8 February 2027 | Terminal tax (no tax agent) |
31 March 2027 | Income tax return (with tax agent extension) |
AIM deadlines
If you use AIM, your provisional tax is paid more regularly based on your actual results. If you file GST monthly, your AIM instalments are monthly. For most other businesses, AIM is filed bi-monthly, even if your GST is filed six monthly.
Period | Due Date |
1 April – 31 May 2026 | 29 June 2026 |
1 June – 31 July 2026 | 28 August 2026 |
1 August – 30 September 2026 | 28 October 2026 |
1 October – 30 November 2026 | 15 January 2027 |
1 December 2026 – 31 January 2027 | 1 March 2027 |
1 February – 31 March 2027 | 7 May 2027 |
GST Due Dates (2026–2027)
For most businesses, GST follows a simple rule:
GST returns and payments are due on the 28th of the following month, with two key exceptions:
Period ending 31 March → due 7 May
Period ending 30 November → due 15 January
If a due date falls on a weekend or public holiday, the next working day applies.
Two-Monthly GST
Group A
Period | Due date |
1 April – 31 May 2026 | 29 June 2026 |
1 June – 31 July 2026 | 28 August 2026 |
1 August – 30 September 2026 | 28 October 2026 |
1 October – 30 November 2026 | 15 January 2027 |
1 December 2026 – 31 January 2027 | 1 March 2027 |
1 February – 31 March 2027 | 7 May 2027 |
Group B
Period | Due Date |
1 March – 30 April 2026 | 28 May 2026 |
1 May – 30 June 2026 | 29 July 2026 |
1 July – 31 August 2026 | 30 September 2026 |
1 September – 31 October 2026 | 30 November 2026 |
1 November – 31 December 2026 | 28 January 2027 |
1 January – 28 February 2027 | 29 March 2027 |
Monthly GST
Period | Due Date |
April 2026 | 28 May 2026 |
May 2026 | 29 June 2026 |
June 2026 | 28 July 2026 |
July 2026 | 28 August 2026 |
August 2026 | 28 September 2026 |
September 2026 | 28 October 2026 |
October 2026 | 30 November 2026 |
November 2026 | 15 January 2027 |
December 2026 | 28 January 2027 |
January 2027 | 1 March 2027 |
February 2027 | 29 March 2027 |
March 2027 | 7 May 2027 |
Six-Monthly GST
January & July Filing
Period | Due Date |
1 February – 31 July 2026 | 28 August 2026 |
1 August 2026 – 31 January 2027 | 1 March 2027 |
February & August Filing
Period | Due Date |
1 March – 31 August 2026 | 30 September 2026 |
1 September 2026 – 28 February 2027 | 29 March 2027 |
March & September Filing
Period | Due Date |
1 April – 30 September 2026 | 28 October 2026 |
1 October 2026 – 31 March 2027 | 7 May 2027 |
April & October Filing
Period | Due Date |
1 May – 31 October 2026 | 30 November 2026 |
1 November 2026 – 30 April 2027 | 28 May 2027 |
May & November Filing
Period | Due Date |
1 June – 30 November 2026 | 15 January 2027 |
1 December 2026 – 31 May 2027 | 28 June 2027 |
A few important notes
These dates are based on standard IRD filing and payment rules. If your business has a non-standard balance date or uses a different tax method, your dates may be different. If a due date falls on a weekend or public holiday, the next working day applies.
If you are ever unsure, it is worth checking your myIR account or getting advice before the deadline rolls around.
If you prefer to go straight to the source, IRD has a full list of key dates available here: https://www.ird.govt.nz/index/key-dates
Final Thoughts
Tax deadlines don’t have to sneak up on you.
A bit of forward planning (even just knowing what’s coming next) can make a big difference to your cash flow, stress levels and avoiding penalties.
If you’d like help staying on top of your GST or income tax obligations, we’re here to make it simple. Contact us at 09 431 3068 or email support@mytwocents.nz. We’d love to help you stay ahead of your tax deadlines and keep everything on track.
About the Author
Haley Reyners is the founder of My Two Cents Accounting & Advisory and a Certified ICNZB Master Bookkeeper® — one of the highest recognitions in New Zealand’s bookkeeping profession. With over 20 years of experience, she’s passionate about helping small business owners find clarity, confidence, and calm in their finances. Haley leads her team with personality and purpose, breaking down complex accounting talk into everyday language that makes sense.
