The New Zealand scheme has two deadlines that cannot be missed, one for approval and one for the supplementary return, and both are fixed by reference to the income year and the income tax return. Apply for general approval by the last day of the 3rd month after the end of the income year. File the supplementary return within 30 days after the income tax return due date, or the extension of time due date. This page sets out the dates, what can be changed, and a calendar for the standard 31 March balance date.
Registration and notification
There is no registration, but there is approval, and approval is a condition of the credit. Most claimants apply for general approval of their activities by the last day of the 3rd month after the end of the income year: 30 June for a 31 March balance date. Significant performers, broadly those expecting more than NZ$2 million of eligible expenditure, may instead apply for criteria and methodologies approval, which must be sought by the last day of the 6th month before the end of the first income year it relates to, 30 September for a 31 March balance date. General approval can cover up to 3 income years for continuing activities, but new activities in a later year need a new or varied application by that year's deadline.
Claim deadline
| Item | Deadline | Late? |
|---|---|---|
| General approval application | Last day of the 3rd month after the end of the income year | No. Inland Revenue does not accept late general approval applications |
| Criteria and methodologies approval | The last day of the 6th month before the end of the first income year it relates to | No |
| Income tax return | 7 July after a 31 March balance date, or 31 March of the following year with a tax agent's extension of time | Late filing penalties; the supplementary return deadline is tied to the due date, not the filing date |
| R&D supplementary return | Within 30 days after the income tax return due date or the extension of time due date | No. The supplementary return must be filed by its due date |
| Correcting a supplementary return | Within the 4 year time bar, for approved activities only | Within the time bar |
| Records | 7 years | Not applicable |
The supplementary return deadline follows the return due date, so a business with an extension of time has until 30 April of the second year after the balance date, while a business without one has until 6 August of the first. Filing the income tax return early does not shorten the window.
Amendments and late claims
Varying an approval. Where activities change during the year, apply to vary the general approval before the supplementary return. Activities carried out but not approved earn no credit, however eligible they would have been.
Correcting the supplementary return. Expenditure on approved activities that was understated can be corrected by requesting an amendment within the time bar, generally 4 years from the end of the tax year in which the return was filed. Inland Revenue can likewise reassess within that period, and without limit for fraud or wilful omission.
Late applications. Inland Revenue does not accept late general approval applications.
Carry forward. Credit not refunded and not used against the year's tax carries forward to later years, subject to shareholder continuity requirements for companies.
Calendar for a typical year end
For a hypothetical company, Marlborough Sensors Limited, with a 31 March 2026 balance date and a tax agent with an extension of time.
| When | What happens |
|---|---|
| April 2025 to March 2026 | R&D performed; records and timesheets kept by activity |
| By 30 September 2025 | Criteria and methodologies application, if Marlborough were a significant performer |
| By 30 June 2026 | General approval application in myIR |
| Before the supplementary return | Any variation of the approval for activities that changed |
| By 31 March 2027 | IR4 income tax return under the extension of time |
| By 30 April 2027 | R&D supplementary return |
| Mid 2027 | Credit applied and refundable amount paid |
| To 31 March 2031 | Time bar for amendments and reassessment |
| To 2034 | Records retained for 7 years |
A company without a tax agent would file its return by 7 July 2026 and its supplementary return by 6 August 2026, nine months earlier.
Common questions
We applied for approval late. Is the year lost? Yes. Inland Revenue does not accept late general approval applications.
Does approval for 3 years mean one supplementary return? No. A supplementary return is filed every year within 30 days of that year's return due date.
Our balance date is 30 June. When is general approval due? By 30 September, the last day of the 3rd month after the income year.
We changed our balance date. Which deadline applies? The deadlines follow the income year as adjusted, so a transitional period has its own approval and supplementary return dates; confirm them with Inland Revenue before relying on the usual pattern.
Related pages
Official sources
Educational content only, not tax advice. See the disclaimer.