R&D Tax Relief: The Claim Notification Form Is Being Scrapped
Index:
R&D Claim Notification Form Scrapped from 1 April 2027: Do You Still Need to Notify, and Can a Missed Claim Be Rescued?
The R&D Claim Notification Form (CNF) is abolished for research and development claims made on or after 1 April 2027. If your claim will reach HMRC before that date and you are a first-time or returning claimant, you must still notify within six months of your period end. If you missed a deadline, a claim made after 1 April 2027 may revive the relief.
This guide reflects the position for claims made in the 2026/27 tax year and the rules announced in the Budget on 28 October 2026. It applies to companies across the UK. Corporation Tax and R&D relief work the same way in Scotland, Wales and Northern Ireland.
What exactly is changing?
The Claim Notification Form is an advance notice telling HMRC that your company intends to claim R&D relief. It has been required since accounting periods beginning on or after 1 April 2023, for first-time claimants and for companies that had not claimed within the previous three years.
HMRC's policy paper on improving the R&D customer experience confirms that companies making R&D claims on or after 1 April 2027 will no longer need to submit one. The change will be made by amending the Corporation Tax Act 2009 in Finance Bill 2026-27. The Additional Information Form (AIF), the detailed project and cost breakdown filed for every claim, stays. It will be simplified from autumn 2027.
The detail that matters is that the trigger is the date the claim is made, not the accounting period. A claim is made when HMRC receives the Company Tax Return (CT600) or the amended return that contains it.
Do you still need to notify before 1 April 2027?
You still need to notify if your claim will reach HMRC before 1 April 2027 and the notification rules apply to you. HMRC's guidance on telling HMRC you plan to claim R&D relief sets out the existing test:
● When notification applies: you must notify if this is your first claim, or if your last claim was more than three years before the last day of the notification period.
● The deadline: the notification period ends six months after the end of your period of account. A late notification makes the claim invalid.
● The exception: you do not need a separate notification if the claim itself reaches HMRC by that same six-month date.
For year ends falling between May and September 2026, the remaining notification deadlines are:
Period of account ends | Notification deadline |
31 May 2026 | 30 November 2026 |
30 June 2026 | 31 December 2026 |
31 July 2026 | 31 January 2027 |
31 August 2026 | 28 February 2027 |
30 September 2026 | 31 March 2027 |
Each of these companies faces a choice. If you want the cash early and file your CT600 before 1 April 2027, the notification is required. If you file on or after 1 April 2027, HMRC's guidance says no notification is needed.
Pro Tax Accountant's view is that you should notify anyway. The form is free, it commits you to no figure, and Finance Bill 2026-27 has not yet been enacted. A notification that turns out to be unnecessary costs you nothing; a missing one, if the law or your filing date changes, costs the whole claim.
R&D Tax Relief: CNF Deadline & Claim Rescue Checker
This interactive tool helps you navigate the upcoming abolition of the Claim Notification Form (CNF) to determine exactly how the new rules impact your company's research and development claim. It instantly clarifies whether you still need to advance notify HMRC before the 1 April 2027 cut-off, or if a previously missed deadline can be legally rescued under the latest Finance Bill provisions. To use the checker, simply select your period of account end date, your current notification status, and your intended Corporation Tax (CT600) filing date from the drop-down menus. The widget will then generate a bespoke summary outlining your precise deadlines and the necessary next steps to safely secure your tax relief.
Can a missed notification be rescued?
Possibly, and this is the most valuable point in the change. A claim made on or after 1 April 2027 does not need a notification under HMRC's guidance, even for a period whose notification window has already closed. The limit is the ordinary claim time limit.
HMRC's Corporate Intangibles Research and Development Manual at CIRD81800 sets that limit: the claim must be made within two years beginning with the last day of the period of account, for periods of up to 18 months. Periods ending on or after 2 April 2025 are therefore the ones that can still be claimed after 1 April 2027.
Year end (notification missed) | Claim time limit | Window from 1 April 2027 |
31 March 2025 | 30 March 2027 | None, time runs out first |
30 April 2025 | 29 April 2027 | 1 to 29 April 2027 |
31 December 2025 | 30 December 2027 | 1 April to 30 December 2027 |
31 March 2026 | 30 March 2028 | 1 April 2027 to 30 March 2028 |
Example: a manufacturing company with a 31 March 2026 year end spent £150,000 on qualifying R&D. It missed its 30 September 2026 notification deadline. Under the merged scheme, the expenditure credit is 20%, so £30,000. The credit is taxable, so a company paying Corporation Tax at the 25% main rate keeps £22,500. A claim made on or after 1 April 2027, and by 30 March 2028, can include that £22,500 without any notification.
The answer changes if the company files its CT600 for that year before 1 April 2027. The claim would then be made under the old rules and would be invalid. If the company has already filed without an R&D claim, it can add one by amending the return after 1 April 2027, within the same time limit.
The Treasury expects real money to flow from this. Removing a single form costs £45 million in 2027/28 and £70 million by 2031/32 in the Budget costings. That figure only makes sense if valid claims that the notification rule would have blocked go through instead.
Finance Bill 2026-27 is not yet law, and its final wording will settle whether every late period benefits. Until Royal Assent, treat a rescue as likely rather than certain.
What has not changed
The Additional Information Form must still be filed for every R&D claim, under the requirements of The Research and Development (Additional Information) Regulations 2023. Without it, HMRC can remove the claim from your return. The simplified version is due from autumn 2027, so claims made between 1 April 2027 and then use the existing form.
Removing the notification step also does not reduce HMRC's checks. HMRC's Research and Development Tax Credits Statistics for September 2026 show 40,325 claims in 2024/25, down 17% on the previous year. First-time claimants under the SME scheme fell 53% to 3,405 in 2023/24. HMRC does not attribute that fall to any single cause. But the scrutiny that came with the 2023 reforms stays in place through the AIF and HMRC's enquiry work.
When to get help
Whether to file before or after 1 April 2027 is a cash-flow decision. Filing a notification is simple. It becomes harder in three situations:
● you have a missed deadline and need to know whether the time limit still allows a claim;
● your period of account is longer than 12 months, so the notification and claim dates run from different points; or
● your group has several companies with different claim histories.
Pro Tax Accountant's R&D tax relief service checks your claim history against the three-year test and works out the notification and time-limit dates for each period. It prepares the Additional Information Form and the technical and cost report, and files the claim in the CT600 or an amended return on the date that keeps the relief valid.
Download FREE Executive Briefing: Scrapping the UK R&D Claim Notification Form & Administrative Modernisation (By PTA)
What to do next
Before your next notification deadline, at the latest 31 March 2027: submit the CNF for any period whose six-month window ends before 1 April 2027, even if you plan to claim later.
Before filing any CT600 before 1 April 2027: check that the notification is in place for any R&D claim in it.
By 31 March 2027: list any period ending on or after 2 April 2025 where a notification was missed, with its two-year time limit.
From 1 April 2027, before each time limit: make the rescued claim through the return or an amended return, with the AIF submitted first or at the same time.
When the Finance Bill 2026-27 clauses are published: confirm the transitional wording before relying on a rescue.
FAQs
We filed our notification but then didn't claim. Do we need to do anything?
No. A notification only preserves the right to claim for that period; it does not oblige you to claim. If you later decide to claim, the ordinary two-year time limit applies. From 1 April 2027 the notification simply stops being relevant to future claims.
Does the change apply to large companies as well as SMEs?
Yes. The notification requirement applied to any company claiming under the merged R&D expenditure credit scheme or Enhanced R&D Intensive Support (ERIS), whatever its size. Its removal from 1 April 2027 applies to all of them in the same way.
HMRC removed one of our previous R&D claims. Does that matter after April 2027?
Under the current rules, a claim HMRC removed from your return does not count as a previous claim, so you would have to notify for the next period. From 1 April 2027 that question no longer arises, because no claim made on or after that date needs a notification. Any enquiry into the earlier claim continues separately.
Our accounting period is 15 months long. When is our deadline?
The notification period runs to six months after the end of the period of account, and the claim time limit runs two years from its last day for periods of up to 18 months. A 15-month period of account is split into two accounting periods for Corporation Tax, but the deadlines follow the period of account. If either deadline falls before 1 April 2027, notify by it to be safe.
About the Author:
Adil Akhtar, ACMA, CGMA, FCMA (membership ID is 990250923) serves as CEO and Chief Accountant at Pro Tax Accountant, bringing over 18 years of expertise in tackling intricate tax issues. As a respected tax blog writer, Adil has spent more than eighteen years delivering clear, practical advice to UK taxpayers. He also leads Advantax Accountants (registered with Companies House), combining technical expertise with a passion for simplifying complex financial concepts, establishing himself as a trusted voice in tax education.
Email: adilacma@icloud.com
Disclaimer: This article sets out the general position under UK tax law for the 2026/27 tax year. The information has been checked against HMRC guidance and other official sources at the date shown above, and is reviewed when the rules change. Tax legislation is complex and outcomes depend on your individual circumstances, so this article is provided for general information and does not constitute advice on which you should act. Any figures or worked examples are illustrative. Before making any decision, obtain advice specific to your situation from a qualified professional. Pro Tax Accountant accepts no liability for loss arising from reliance on this article alone.
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