UK R&D Tax Credits Guide: How to Prepare Your Claim

Understand UK R&D tax relief, what HMRC expects and how to prepare your claim information — step by step.

R&D tax relief helps eligible UK companies reduce the financial cost of qualifying research and development. Preparing a claim involves more than identifying innovation or adding up project expenses. You need to explain the scientific or technological work undertaken, identify qualifying expenditure and provide the information HMRC requires.

1. What are R&D tax credits?

R&D tax credits, also known as R&D tax relief, are UK Corporation Tax incentives designed to support companies carrying out qualifying research and development. Depending on the applicable scheme and company circumstances, relief may take the form of an expenditure credit, enhanced deduction or payable tax credit.

Not every innovative project qualifies. HMRC focuses on whether the work sought an advance in science or technology by resolving scientific or technological uncertainty.

2. Who can claim R&D tax relief?

Generally, the claimant must be a company within the scope of UK Corporation Tax that has incurred qualifying R&D expenditure. Companies in manufacturing, engineering, biotechnology, software, energy, agriculture and other sectors may undertake qualifying work. The industry itself does not determine eligibility.

A project can be commercially successful without qualifying. An unsuccessful technical project may qualify if the relevant conditions are met.

Learn more: R&D Tax Relief Eligibility.

3. Which R&D tax relief schemes apply?

For accounting periods beginning on or after 1 April 2024, the principal schemes are:

The merged R&D scheme

An expenditure-credit-based scheme available to eligible companies undertaking qualifying R&D.

Enhanced R&D Intensive Support (ERIS)

Additional support for eligible loss-making R&D-intensive SMEs, subject to applicable conditions.

Older accounting periods may fall under previous SME R&D tax relief or RDEC rules. The correct scheme depends on the accounting period and company circumstances.

4. What makes a project eligible?

An advance in science or technology

The project must seek to advance overall knowledge or capability in a field of science or technology, rather than simply improve what the individual company knows.

Scientific or technological uncertainty

The project must involve uncertainty that a competent professional in the field could not readily resolve using existing knowledge or established methods.

For example, developing a technically new manufacturing process to achieve performance that existing methods cannot reliably deliver may involve qualifying uncertainty. Routine customisation and ordinary troubleshooting do not qualify merely because they require skilled work.

Learn more: R&D Tax Relief Eligibility.

5. What costs may qualify?

Depending on the scheme and rules, qualifying expenditure may include:

• Certain employee and employer staffing costs
• Qualifying externally provided workers
• Eligible contracted-out R&D expenditure
• Consumable materials used in R&D
• Relevant software costs
• Certain data licence and cloud computing costs
• Other expenditure categories specifically permitted by HMRC

Only the qualifying proportion should be included where a cost relates partly to R&D and partly to other activities.

Learn more: Qualifying R&D Expenditure.

6. How to prepare your R&D tax relief claim

Step 1 — Identify your R&D activities

Review projects undertaken during the relevant accounting period. Identify the scientific or technological advances sought and uncertainties encountered.

Step 2 — Explain your technical work

Describe what was already known, why established approaches were insufficient and what your team did to resolve the uncertainty. Include decisions, experiments, tests, difficulties and results.

Step 3 — Organise supporting evidence

Gather project records, technical reports, design changes, test results and other contemporaneous evidence. Explain how records support your technical descriptions.

Step 4 — Identify and allocate qualifying costs

Collect financial information, identify potentially qualifying categories and calculate the proportion attributable to R&D. Document the allocation method.

Step 5 — Review the claim information

Check technical explanations, project dates, cost calculations and supporting records. Confirm the scheme and filing requirements.

Step 6 — Complete the required HMRC filing

An R&D claim is made through the company's Corporation Tax filing process. Depending on the claim date and applicable rules, additional information and notification requirements may apply. You may complete the filing yourself or use an accountant or tax advisor.

7. What information does HMRC require?

HMRC expects information sufficient to support the claim, potentially including company and accounting-period details, qualifying project descriptions, advances, uncertainties, work undertaken, qualifying expenditure, calculations and records.

The Additional Information Form is currently a key part of the process. HMRC announced plans to simplify it from autumn 2027.

8. When is the deadline?

For most standard periods of account, the R&D claim deadline is two years after the end of the period. Different calculations apply to longer periods, and some requirements have earlier deadlines.

Learn more: R&D Claim Deadlines.

9. Can you prepare the claim yourself?

Yes. A company does not have to appoint a specialist R&D tax advisor to prepare its claim. The company remains responsible for accuracy and supportability. Professional assistance can be valuable for complex eligibility, expenditure or tax calculation questions.

Official HMRC references

• Meaning of R&D for tax purposes
• Make a claim for R&D tax relief
• Check what R&D costs you can claim

General information, not tax advice. Eligibility and filing requirements depend on circumstances and applicable rules.