Ireland: Claim integrity measures | Research Credit Integrity Alliance

Irish law and Revenue guidance set several requirements that a company must meet before it can receive the research and development (R&D) corporation tax credit. This page lists them in the order a company meets them: notification before the claim, the claim itself, the records behind it, and the rules on payment and correction.

Overview

Measure	Legal basis	Who it applies to
Pre-filing notification at least 90 days before the claim	Section 766C(17) TCA 1997	First-time claimants and companies with no claim in the previous three accounting periods1
Claim made in the corporation tax return within 12 months	Section 766C(9)(a)	All claimants1
Specified expenditure details in the claim	Section 766C(9)(b)	All claimants1
Valid claim before payment or offset	Section 766C(12) and (14)	All claimants1
Records for the science test and the accounting test	Section 766(1)(a), definition of "qualified company"	All claimants2
Revenue may examine after payment	Section 766C(16)	All claimants1

Before the claim: pre-filing notification

For accounting periods beginning on or after 1 January 2024, a company that has not claimed the R&D credit in any of its previous three accounting periods must notify Revenue in writing, on a prescribed form, at least 90 days before the claim is made.13 The form asks for the company's details, the number of employees carrying on R&D, the number of R&D projects, grant or other assistance, and a description of the qualifying activities.3 Revenue may ask for additional information, explanations and particulars.1 The pre-filing notification page covers this in detail.

The claim

A claim must be made in the corporation tax return within 12 months from the end of the accounting period in which the expenditure was incurred.1 Revenue's guidance states that a company should claim through Form CT1 on the Revenue Online Service (ROS) only where it is satisfied it can meet the requirements of the legislation and has kept the necessary records.2

The company must give, in the return:

the amounts of each instalment claimed and whether each is to be treated as an overpayment of tax or paid to the company;2
its R&D expenditure on plant or machinery, the emoluments of employees carrying on R&D activities, and its remaining R&D expenditure, net of grant funding;12
any non-refundable credits carried forward from earlier claims.1

Companies that filed a pre-filing notification should tick the box on the R&D panel of Form CT1 to show it was submitted.3 Related returns, such as iXBRL financial statements where required, must also be filed for the claim to be processed.2 No supporting R&D documentation is submitted with the return, but it may be requested later.2

The valid claim rule

No amount of the credit is paid or offset unless a valid claim has been made.1 A valid claim is one that provides all the information Revenue may reasonably require to determine whether, and to what extent, the credit is due for the accounting period.1 Revenue states that the concept is not new and that it was written into section 766C so that the payment timelines operate as intended.2

Once a valid claim is made, the credit is paid or offset in three instalments within 48 months.1

Records: the science test and the accounting test

Revenue states that a company must be able to show its claim satisfies two tests: that the activity is qualifying R&D (the "science test") and that the costs of the activity have been properly tracked and accounted for (the "accounting test").2 Contemporaneous records, on paper or electronic, must be available for inspection by Revenue officials.2

Test	Examples of records Revenue lists
Science test	Description of the activities and methods; field of science or technology; the advancement sought; the uncertainty to be resolved; evidence that the advance was not already achieved; details of the systematic investigation; qualifications of the project manager and staff2
Accounting test	Project start and end dates; project plan and progress; personnel and time allocated; location costs; payments to universities and subcontractors; methods of apportioning expenditure2

Records must be made on a timely and consistent basis and kept continuously, and the company must be able to give reliable assurances about their integrity, including the author and date of creation of each record.2 Revenue publishes a suggested file layout for an R&D claim, based on its experience of reviewing claims and on feedback from compliance officers and independent experts. Revenue states that there is no requirement to keep documentation in that format.2

After payment

Revenue may examine a claim, and make or amend an assessment, after the credit has been paid or offset.1 Revenue may consult independent experts on the science test.4 The reviews and audits and expert consultation pages explain how.

Key employees

A company may surrender part of the credit to key employees. It must make the claim in a form Revenue may prescribe and notify each key employee in writing of the amount surrendered. If the amount is later found not to be authorized, the company must notify the employee in writing of the correct amount.1

What the measures do not cover

The measures above concern the company, its activities and its expenditure. None of the details required by section 766C(9)(b) or 766C(17) identifies a person who prepared the claim or how that person was paid.13 See preparer identification.

Sources

Revenue Commissioners, Notes for Guidance, Taxes Consolidation Act 1997, Finance Act 2025 edition, Part 29, section 766C, subsections (2) to (4), (9), (11), (12), (14), (16) and (17). 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 29-02-03, Research and Development (R&D) Corporation Tax Credit (last updated April 2026), sections 8, 8.1, 8.2, 8.4, 8.6.2 and Appendix 3. 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, Research and Development Corporation Tax Credit: Pre-filing Notification Form in respect of a claim to be made under section 766C TCA 1997, form and notes. https://www.revenue.ie/en/companies-and-charities/documents/rd-form-766c.pdf (accessed 11 October 2026). Back
Revenue Commissioners, Tax and Duty Manual Part 29-02-05, Research and Development (R&D) Corporation Tax Credit: Appointment of expert to assist in audits (last updated August 2025), Introduction. https://www.revenue.ie/en/tax-professionals/tdm/income-tax-capital-gains-tax-corporation-tax/part-29/29-02-05.pdf (accessed 11 October 2026). Back