Ireland: Disputes and appeals | Research Credit Integrity Alliance

When Revenue reduces or refuses a research and development (R&D) corporation tax credit claim, the company can settle with Revenue, ask Revenue to review how the case was handled, or appeal to the Tax Appeals Commission. This page sets out those routes and the time limits in the Taxes Consolidation Act 1997 (TCA 1997).

How a reduced claim becomes appealable

Where Revenue concludes that a claim was not authorized, it may make an assessment charging the company to tax under Case IV of Schedule D on an amount equal to four times the unauthorized amount, with interest from the date the credit was paid or offset.1 Because income chargeable under Case IV of Schedule D is taxed at 25 percent, the tax on that charge equals the unauthorized amount.2 More generally, Revenue may make or amend an assessment after the credit has been paid or offset.1 An appeal is made against the assessment or other appealable decision. No appeal lies against a company's own self-assessment, or against the amount of a credit included in it.3

Settlement and review within Revenue

Revenue's Code of Practice for Revenue Compliance Interventions states that, where a difference of opinion arises in a compliance intervention, Revenue will respect the taxpayer's right to request a review or to use the statutory appeal procedure.4

Review of Revenue's handling. Revenue's review procedures apply only to complaints about how Revenue handled a case. Disputes about a liability to tax are for the Tax Appeals Commission.4
Settlement. An appeal may be settled by agreement between the parties. The agreement must be in writing, either party may repudiate it within 21 days, and the appeal is then treated as withdrawn. Revenue gives effect to the agreement, for example by amending the assessment.5

Appeal to the Tax Appeals Commission

The Code describes the Tax Appeals Commission as independent and states that a taxpayer may appeal to it against Revenue's findings in relation to a revised assessment or estimate of tax.4 In law, the appeal is made to the Appeal Commissioners under Part 40A of the TCA 1997.5

Step	Rule	Source
Time limit	Within 30 days after the date of the notice of assessment	Section 959AF(1)3
Form of appeal	Written notice to the Appeal Commissioners, with a copy of Revenue's notice attached	Section 949I5
Contents	Name and address, tax reference number, the matter appealed, detailed grounds, and any other particulars required	Section 949I(2)5
Grounds	An appellant may not rely on grounds not stated in the notice unless the Commissioners are satisfied there was good reason	Section 949I(6)5
Late appeal	May be accepted within 12 months of the deadline for absence, illness or other reasonable cause; longer only if further conditions are met, including payment of the tax charged	Section 949O5
Tax not under appeal	Any liability not under appeal must be paid before an appeal against an assessment can be lodged	Code of Practice, section 4.11.24

Where an assessment is appealed, the Code states that statutory interest is chargeable only when the tax in dispute is determined, and that tax-geared penalties can only be quantified when the tax is determined.4

Hearings and determinations

Hearings are held in public by default, but must be held in private where the appellant asks, and a request can be made up to 14 days after being notified of the hearing.5 The Appeal Commissioners must publish a report of each determination on the internet within 90 days of notifying the parties, in a way that, as far as possible, conceals the identity of a person whose affairs were treated as confidential.5

Experts at the Tax Appeals Commission

Where a claimant company disputes the opinion of an independent expert engaged by Revenue on the science test, Revenue's manual states that the expert may be required to give evidence before the Tax Appeals Commission or a court.6

A separate right of appeal concerns the choice of expert. Before disclosing information to an expert, Revenue must tell the company who it intends to consult and what it intends to disclose. Revenue will not make the disclosure if the company shows, to Revenue's satisfaction or on appeal to the Appeal Commissioners, that it could prejudice the company's business.7 See expert consultation.

Appeal to the High Court

A determination of the Appeal Commissioners is final and conclusive unless it is appealed to the High Court.5 A party may appeal only on the ground that the Commissioners erred on a point of law, not on the facts. The party must send a written notice to the Appeal Commissioners asking them to prepare a "case stated" for the High Court, identifying the point of law, within 21 days after the determination is sent to the parties, and must send a copy to the other party.5

Published decisions

This page does not yet cite any published Tax Appeals Commission determination or court decision on the R&D credit.

Summary

Route	Purpose	Key time limit
Revenue review procedures	Complaints about Revenue's handling of a case4	Not stated in the sources reviewed
Settlement by agreement	Ends the appeal by written agreement5	21 days to repudiate5
Tax Appeals Commission	Disputes about liability4	30 days after the notice of assessment3
High Court	Errors on a point of law5	21 days to request a case stated5

Sources

Revenue Commissioners, Notes for Guidance, Taxes Consolidation Act 1997, Finance Act 2025 edition, Part 29, section 766C, subsections (10) and (16). https://www.revenue.ie/en/tax-professionals/documents/notes-for-guidance/tca/part29.pdf (accessed 11 October 2026). Back
Revenue Commissioners, Tax and Duty Manual Part 02-02-02, The charge to and rates of Corporation Tax (last reviewed January 2024), sections 5 and 8, section 21A(3)(a) TCA 1997. https://www.revenue.ie/en/tax-professionals/tdm/income-tax-capital-gains-tax-corporation-tax/part-02/02-02-02.pdf (accessed 17 October 2026). Back
Revenue Commissioners, Notes for Guidance, Taxes Consolidation Act 1997, Finance Act 2025 edition, Part 41A, sections 959AF and 959AG. https://www.revenue.ie/en/tax-professionals/documents/notes-for-guidance/tca/part41a.pdf (accessed 11 October 2026). Back
Revenue Commissioners, Code of Practice for Revenue Compliance Interventions (effective 1 May 2022), sections 4.11, 4.11.1 and 4.11.2. https://www.revenue.ie/en/tax-professionals/documents/code-of-practice-revenue-compliance-interventions.pdf (accessed 11 October 2026). Back
Revenue Commissioners, Notes for Guidance, Taxes Consolidation Act 1997, Finance Act 2025 edition, Part 40A, sections 949I, 949O, 949V, 949Y, 949AO, 949AP and 949AQ. https://www.revenue.ie/en/tax-professionals/documents/notes-for-guidance/tca/part40a.pdf (accessed 11 October 2026). Back
Revenue Commissioners, Tax and Duty Manual Part 29-02-03, Research and Development (R&D) Corporation Tax Credit (last updated April 2026), section 10. https://www.revenue.ie/en/tax-professionals/tdm/income-tax-capital-gains-tax-corporation-tax/part-29/29-02-03.pdf (accessed 11 October 2026). Back
Revenue Commissioners, Notes for Guidance, Taxes Consolidation Act 1997, Finance Act 2025 edition, Part 29, section 766, subsection (7)(b). https://www.revenue.ie/en/tax-professionals/documents/notes-for-guidance/tca/part29.pdf (accessed 11 October 2026). Back