How do I make an R&D tax credit claim?
Answered 17 March 2026
Here is a comprehensive answer on how to make an R&D tax credit claim in the UK.
How to Make an R&D Tax Credit Claim
What the law says
There are two main types of R&D relief claim, each requiring a formal claim:
-
R&D Expenditure Credit (RDEC): To obtain an R&D expenditure credit, the company must make a claim via Part 9A of Schedule 18 to the Finance Act 1998.
-
R&D Tax Credit (SME/ERIS scheme): To obtain an R&D tax credit in respect of a Chapter 2 surrenderable loss, the company must similarly make a claim under Part 9A of Schedule 18 to the FA 1998.
Claim Notification requirement: For accounting periods beginning on or after 1 April 2023, a company may not make an R&D claim after the end of the claim notification period unless at least one of the following applies:
- The company has made an R&D claim during the three years ending with the last day of the claim notification period;
- The company makes a claim notification within the claim notification period; or
- The accounting period falls within the same period of account as another period for which an R&D claim or claim notification has been made.
The claim notification period runs from the first day of the period of account and ends six months after the last day of that period of account.
Once a valid claim is made, an officer of HMRC must pay the company the amount of the credit. Importantly, the right to be paid an R&D credit cannot be assigned, and HMRC may not pay the credit to a nominee (other than in limited circumstances).
HMRC guidance / practice
The claim process involves up to three distinct steps:
Step 1 – Claim Notification Form (if required)
If you are submitting your first R&D claim, have had a claim rejected, claimed by amendment, or are claiming for an accounting period beginning on or after 1 April 2023, you may need to submit a Claim Notification Form before making your claim. The time limit for submitting the notification is 6 months after the end of the period of account.
Step 2 – Additional Information Form (AIF) — mandatory from 8 August 2023
For all R&D claims made on or after 8 August 2023, a company must submit an Additional Information Form (AIF) before the Company Tax Return is submitted. This applies to all schemes (RDEC, SME, ERIS). The AIF is submitted online via GOV.UK. All companies claiming R&D relief are required to complete an AIF for each accounting period in which a claim is made.
Step 3 – Company Tax Return (CT600)
The actual claim is made in the Company Tax Return (CT600) or an amended return, subject to a time limit of 2 years from the end of the accounting period (for periods beginning before 1 April 2023), or 2 years from the last day of the period of account (for periods beginning on or after 1 April 2023).
For accounting periods ending on or after 1 April 2015, entries are required in boxes 530, 545, 570, 605 and 880 of the CT600 (version 3). Box 530 is completed via the supplementary page CT600L, which must be submitted whenever a claim for a Payable Tax Credit or R&D Expenditure Credit is made.
All R&D claims from 1 April 2023 (including amended claims) must be submitted digitally. Where a claim is made by amendment, it must include a completed CT600 and a corporation tax computation.
Late claims
Any late claims must be made in accordance with Statement of Practice SP05/01 and will be reviewed by an R&D Specialist and a Grade 6 Decision Maker.
Summary of the process:
| Step | Action | Timing |
|---|---|---|
| 1 | Submit Claim Notification Form (if required) | Within 6 months of end of period of account |
| 2 | Submit Additional Information Form (AIF) online | Before filing the CT600 |
| 3 | File CT600 (with CT600L) including the R&D claim | Within 2 years of end of accounting period |
Citation sources
Part 13 ... expenditure on research and development Chapter 2 Relief for loss-making, R&D-intensive SMEs Tax credit: entitlement and payment Entitlement to and payment of tax credit 1054 1 A company is entitled to an R&D tax credit for an accounting period if it has a Chapter 2 surrenderable loss in the period (see section 1055). 2 For the company to obtain an R&D tax credit in respect of all or part of the Chapter 2 surrenderable loss it must make a claim (see Part 9A of Schedule 18 to the FA 1
Statutory framework FA98/SCH18/Para. 83EA was inserted by F(No. 2)A23/S10 & F(No. 2)A23/SCH1/Para. 13 with effect for claims to R&D relief made on or after 1 August 2023 (in practice, it only affects claims made on or after 8 August 2023 – see below). For guidance and examples showing when a claim is “made”, please see CIRD81805. Para. 83EA gives HMRC the power to specify by regulations information to be required in support of a claim to R&D tax relief under either the new merged scheme RDEC (“n
very of relief where a company receives a refund of some qualifying R&D expenditure (CIRD87500). Claims process changes from April 2023 All R&D Claims from 1 April 2023 which include amended claims must be submitted digitally. For accounting periods starting on or after 1 April 2023 some customers will need to submit a Claim Notification form for their R&D claim to be valid. Please see CIRD81800 for more information Tell HMRC that you’re planning to claim Research and Development (R&D) tax re
A claim to R&D can only be made in a Company Tax return or an amended company tax return. For accounting periods which commenced before 1 April 2023, a claim to R&D can be made within the normal time limit of 12 months following the filing date. For a standard 12-month accounting period this will be 2 years from the last day of that accounting period. For accounting periods which commence on or after 1 April 2023, a claim to R&D can be made: within 2 years beginning with the last day of the peri
If you are submitting your first R&D claim, have had an R&D claim rejected, claimed by amendment to your return or claimed for an accounting period beginning on or after 1 April 2023, you may need to submit a claim notification. Companies claiming under all schemes are required to complete an Additional Information Form (AIF) for each accounting period where there is a claim for R&D Relief. Guidance on completing the AIF has been published to help when completing the form. The information provid
Part 13 ... expenditure on research and development Chapter 1A R&D expenditure credit Entitlement and claims Claiming the credit 1042C 1 To obtain an R&D expenditure credit the company must make a claim (see Part 9A of Schedule 18 to the FA 1998). 2 A company may not make the claim (“the RDEC claim”) after the end of the claim notification period unless— a the company has made an R&D claim during the period of three years ending with the last day of the claim notification period, b the company m
Part 13 ... expenditure on research and development Chapter 2 Relief for loss-making, R&D-intensive SMEs Tax credit: entitlement and payment Requirement to make a claim notification 1054A 1 A company may not make a claim under section 1054(2) (an “R&D tax credit claim”) after the end of the claim notification period unless— a the company has made an R&D claim during the period of three years ending with the last day of the claim notification period, b the company makes a claim notification in re
pril 2015, claims are made in version 2 of the Company Tax Return. Link to CT600 Guidance (version 2 of the Company Tax Return) From 1 April 2019 all R&D claims which are made in an amendment to a return need to include a completed CT600 and a corporation tax computation. Most amendments to a return are made through the Corporation Tax Online Service (also known as the COTAX gateway - details are in the COTAX Manual [COM] at COM130001) and already include a completed CT600 and a corporation t