New Zealand: Your responsibility

An adviser can prepare the general approval application, the technical descriptions and the R&D supplementary return, and file them as your tax agent. None of that moves the claim out of the business's name. The return is your business's own, and if Inland Revenue later reduces the credit, your business pays the shortfall. Inland Revenue's own guidance on shortfall penalties treats professional advice you received as a factor in whether reasonable care was taken, not as a defence that moves the penalty.1Source 1Inland Revenue, Shortfall penalties (30 September 2020). The questions on who signs the claim and can we see the full claim before filing? are about making that responsibility real. The people who did the work read the technical descriptions before the return goes in, and the business keeps a copy of what was filed.

• Making the claim. General approval must be applied for in time; Inland Revenue does not accept late applications. The R&D supplementary return is due within 30 days after the income tax return due date.2Source 2Inland Revenue, Research and development tax incentive due dates (1 April 2026). A claim for an earlier year is usually not open at all, so test any offer to claim for past years against these dates (cold calls about unclaimed refunds).
• Inland Revenue's time limit. The Commissioner cannot increase an amount previously assessed after four years from the end of the tax year in which the return was provided. The exceptions are a return that was fraudulent or wilfully misleading, or that omitted income of a particular nature or source.3Source 3Inland Revenue, Standard Practice Statement SPS 20/03, Requests to amend assessments (2 June 2020), paragraph 81, Tax Administration Act 1994 sections 108 and 108A; Inland Revenue Tax Technical, Taxation (Annual Rates, Foreign Superannuation, and Remedial Matters) Act 2014: remedial matters, section 108(2). A claim can therefore be looked at well after the credit has been paid, which is why review support in the engagement letter matters (is review support included?).

If Inland Revenue reduces the credit, the business pays the difference. Interest on underpaid tax runs from the day after the original due date until it is paid.4Source 4Inland Revenue, Interest on overpayments and underpayments (8 July 2026). A shortfall penalty can apply, from 20% of the shortfall for not taking reasonable care, through 20% for an unacceptable tax position and 40% for gross carelessness, to 100% for an abusive tax position and 150% for evasion.1Source 1Inland Revenue, Shortfall penalties (30 September 2020). Whether the adviser's fee comes down too depends on the engagement letter, not on Inland Revenue: see what happens to the fee if the claim is reduced? The engagement letter's liability and indemnity clause is where any contribution from the adviser would be found.

Inland Revenue's guidance on fixing mistakes in a return says to fix it in myIR, in your next return for small differences only, or by asking Inland Revenue to do it, and not to send a replacement return. A voluntary disclosure is telling Inland Revenue what is wrong with a return before it finds out another way.5Source 5Inland Revenue, Fixing mistakes in my return (4 June 2026). Inland Revenue's practice on amending assessments is set out in its standard practice statement SPS 20/03.3Source 3Inland Revenue, Standard Practice Statement SPS 20/03, Requests to amend assessments (2 June 2020), paragraph 81, Tax Administration Act 1994 sections 108 and 108A; Inland Revenue Tax Technical, Taxation (Annual Rates, Foreign Superannuation, and Remedial Matters) Act 2014: remedial matters, section 108(2). A full voluntary disclosure made before the first notice of a pending audit or investigation reduces a shortfall penalty by 75% to 100%; one made after first notice but before the audit starts reduces it by 40%.6Source 6Inland Revenue, Lowering your shortfall penalty (17 June 2021). Take advice before you disclose: the correcting a claim page sets out what to settle first, including what the engagement letter says about the fee on the corrected amount.

If Inland Revenue reviews the claim within the time limit above, it can ask for the evidence behind it. Keep the general approval application, the supplementary return and the income tax return as filed, the technical descriptions, the cost workings, the project and time records they rest on, and the engagement letter. Ask for anything the adviser holds that you do not (ownership of records and work).

• If your claim is reviewed and complaints about an adviser in New Zealand
• Claim reduced on review and if you are charged a penalty
• The true cost of a claim

Sources

1. Inland Revenue, Shortfall penalties (30 September 2020).   Back
2. Inland Revenue, Research and development tax incentive due dates (1 April 2026).  Back
3. Inland Revenue, Standard Practice Statement SPS 20/03, Requests to amend assessments (2 June 2020), paragraph 81, Tax Administration Act 1994 sections 108 and 108A; Inland Revenue Tax Technical, Taxation (Annual Rates, Foreign Superannuation, and Remedial Matters) Act 2014: remedial matters, section 108(2).   Back
4. Inland Revenue, Interest on overpayments and underpayments (8 July 2026).  Back
5. Inland Revenue, Fixing mistakes in my return (4 June 2026).  Back
6. Inland Revenue, Lowering your shortfall penalty (17 June 2021).  Back