The law on the credit is in Chapter 2 of Part 29 of the Taxes Consolidation Act 1997 and the 2004 Regulations. Revenue's reading of it is in the Tax and Duty Manuals, principally Part 29-02-03, which is the document Revenue's own caseworkers and appointed experts work from. The manual does not have the force of law, but a claim that follows it will rarely be in dispute on procedure, and a claim that departs from it needs a reason. This page describes what the guidance covers and how to use it.
What it is
| Document | Covers | Status |
|---|---|---|
| Tax and Duty Manual Part 29-02-03 | The main credit: qualifying companies and activities, the science and accounting tests, qualifying expenditure, subcontracting, grants, the instalments, notification, records and Revenue's approach to review | Revenue guidance, updated periodically; not law |
| Separate Revenue guidance | Revenue publishes separate guidance on the credit for expenditure on buildings and on surrendering credit to key employees | Guidance |
| Revenue.ie pages | Plain-language summary, forms, the pre-filing notification | Guidance |
| Taxes Consolidation Act 1997, sections 766 to 766C | The credit itself | Law |
| S.I. No. 434 of 2004 | Prescribed fields of science and technology and excluded activities | Law |
| Code of Practice for Revenue Compliance Interventions | How Revenue reviews, penalties, disclosures | Revenue code |
Who it applies to
Everyone who prepares or reviews an Irish claim. Revenue caseworkers apply the manual; Revenue's appointed experts are briefed on the science test as the manual describes it; the Tax Appeals Commission reads it as evidence of Revenue's practice while deciding cases on the Act. Companies and advisers use it to structure the claim file, because its headings are the questions Revenue will ask. Where the manual is silent, the Act and the Regulations govern; where the manual appears stricter than the Act, the Act prevails, but the company should expect to argue the point.
How it works
The science test. The manual sets out Revenue's approach: identify the field of science or technology within the prescribed categories; identify the scientific or technological advancement sought, judged against the state of knowledge in the field rather than the company; identify the uncertainty, judged by whether a competent professional could readily resolve it; and show that the activities were systematic, investigative or experimental. It describes the documentation Revenue expects and the use of experts.
The accounting test. The manual explains the meaning of wholly and exclusively, the apportionment of staff costs, the treatment of plant and machinery, the subcontracting and third level caps, the exclusion of grant-funded expenditure and the reconciliation to the accounts.
Procedure. The manual covers the pre-filing notification, the Form CT1 panel, the instalment computation and elections, the surrender to key employees, Revenue's compliance approach and clawbacks.
Keeping up. The manual is revised when the law changes, as it was for the 2023 instalment regime, the 2024 rate increase and the thresholds. Check the version date before relying on a passage, and read the Finance Act changes alongside it; the 35% rate and the €87,500 threshold apply only to the periods the Act specifies.
Worked example
Illustrative example. Moy Pharma Limited, a hypothetical company, prepares its first claim and uses the manual as a checklist:
| Manual heading | What Moy does |
|---|---|
| Qualifying company | Confirms it is within the charge to corporation tax and carries on a trade |
| Science test | For each of three projects, writes the field, the advancement, the uncertainty and the investigation, with pointers to the lab notebooks |
| Accounting test | Apportions chemists' emoluments from timesheets; includes consumables and HPLC equipment; excludes rent and administration |
| Subcontracting | Caps the contract research organisation's invoices at the greater of 15% of own spend or €100,000; issues the written notification |
| Grants | Deducts the Enterprise Ireland grant from the costs it funded |
| Notification | Files the pre-filing notification more than 90 days before the claim |
| Payment | Elects repayment of the first instalment, which is the greater of 50% of the claim or €75,000 |
| Records | Assembles the project file and keeps it for 6 years |
Common questions
Is the manual binding on Revenue? Not in law, but Revenue follows its own published guidance, and a company can rely on it as a statement of practice.
Does Revenue publish decisions on individual claims? No. Tax Appeals Commission determinations are published and are the main public source of applied reasoning.
Can we ask Revenue for an opinion before claiming? Revenue does not operate a pre-approval service for the credit; it will answer technical queries through its usual channels but the claim is assessed when made.
Do the Tax Appeals Commission determinations change the manual? Revenue updates the manual when a determination or a court decision changes its understanding, so a run of determinations on a point tends to appear in the next revision.
Which version applies? The law in force for the accounting period; the manual current at the time of the claim describes Revenue's practice.
Related pages
Official sources
Educational content only, not tax advice. See the disclaimer.