R&D Evidence Templates and Examples for HMRC Claims
Practical records your business can use throughout an R&D project
Last reviewed 21 October 2026Good R&D evidence explains not just what your business developed, but what technical questions it investigated, how it attempted to resolve them and what the results demonstrated.
HMRC does not require every company to use the same project management template. However, businesses must retain sufficient evidence to support the technical and financial information included in their claims.
The following six example record structures can help companies organise that evidence.
These are suggested documentation formats, not official HMRC forms or downloadable Plio templates.
Template 1 — Technical Uncertainty Register
Use a separate record for each significant scientific or technological uncertainty.
| Field | Example |
|---|---|
| Uncertainty ID | UNC-001 |
| Project | Precision coating development |
| Technical discipline | Materials engineering |
| Technical objective | Improve coating adhesion under repeated thermal cycling |
| Unresolved question | Can the required adhesion be achieved without compromising surface performance? |
| Identified date | 12 January 2026 |
| Investigation start | 2 February 2026 |
| Responsible professional | Lead materials engineer |
| Current status | Under investigation |
| Supporting evidence | Laboratory reports and technical reviews |
The register should distinguish the date a difficulty was identified from the date qualifying work to resolve it actually began.
A record should not be labelled as qualifying simply because the business has identified a difficult technical problem.
Template 2 — State of Knowledge and Research References
A technical baseline record helps establish what was already known at the relevant time.
| Field | What to record |
|---|---|
| Baseline date | Relevant start date of the technical investigation |
| Existing methods | Available processes or technologies |
| Published sources | Publication title, author, date, DOI or URL |
| Relevant findings | Technical capabilities and limitations identified |
| Remaining uncertainty | What the sources do not readily resolve |
| Professional conclusion | Why a solution was not readily deducible |
| Review date | Date the research was assessed |
For example, a publication may identify limitations in the performance of an existing coating process.
The business should explain how those limitations relate to its own technical objective.
Important: A publication discovered later can help evaluate an earlier knowledge baseline, but its publication date and relevance must be considered. An absence of search results does not prove that no solution existed.
Template 3 — Experiment and Investigation Log
An experiment log should link technical activities to the uncertainty being investigated.
Illustrative example:
| Date | Investigation | Observation | Next action |
|---|---|---|---|
| 5 February | Test standard coating process | Adhesion below target | Analyse failure mechanism |
| 12 February | Modify curing conditions | Improved initial adhesion | Test thermal cycling |
| 19 February | Perform thermal cycle tests | Degradation after repeated cycles | Examine interface structure |
| 26 February | Evaluate revised formulation | Partial improvement | Repeat testing |
Attach the relevant measurements, drawings, laboratory records, photographs or other supporting files.
A good experiment record explains the technical reasoning for an activity, not merely that someone worked on the project.
Template 4 — Technical Decision and Change Log
R&D projects frequently change direction when initial assumptions prove incorrect.
Recording those decisions can provide useful evidence of the investigation process.
Suggested record:
- Decision date.
- Original technical approach.
- Evidence demonstrating the limitation.
- Alternative approaches considered.
- Reason for selecting the revised method.
- Expected technical result.
- Actual result.
- References to supporting documents.
For example:
Original approach: Use the established coating formulation.
Finding: Repeated thermal cycling caused adhesion loss.
Decision: Investigate an alternative formulation and revised curing process.
Reason: Existing test results showed the original process was not meeting the required technical performance.
Supporting evidence: Tests 003–008 and engineering review dated 26 February.
This record helps show why technical decisions were made during the investigation.
Template 5 — Competent Professional Statement
A competent professional's explanation can help establish why a genuine scientific or technological uncertainty existed.
A suggested statement structure is:
Professional background
Name, role, relevant technical specialism, qualifications or experience, and involvement in the project.
Assessment of existing knowledge
What established methods and technical capabilities were available at the relevant time?
Description of the uncertainty
What could not readily be determined or deduced using that knowledge?
Investigation undertaken
Which technical approaches were evaluated, and why?
Conclusion
What was learned, what remains unresolved and when the relevant uncertainty was resolved or the investigation ceased.
The statement should express the professional's genuine assessment rather than a generic AI-generated claim of eligibility.
Template 6 — Cost Allocation Justification
Record not only the proposed R&D percentage but also why that allocation is reasonable.
| Field | Illustrative entry |
|---|---|
| Employee | Senior development engineer |
| Relevant eligible staffing cost | £48,000 |
| Proposed R&D allocation | 35% |
| Proposed qualifying amount | £16,800 |
| Allocation basis | Employee activity estimate |
| Supporting records | Project activities and monthly technical reports |
| Reviewed by | Finance manager |
| Review date | 15 January 2027 |
A cost allocation justification should explain which activities were included, which were excluded and why the percentage was selected.
The same method should not automatically be applied to every cost category.
See Qualifying R&D Expenditure for the separate eligibility requirements that apply to different expenditure types.
How should the records connect?
A useful R&D evidence chain is:
- Technical uncertainty
- Investigation
- Experimental evidence
- Professional conclusion
- Relevant R&D activities
- Supporting expenditure
For example, if an engineer spends time investigating coating failure, the business should be able to connect the staffing allocation with the relevant experimental activities and project records.
This does not mean every cost must be linked to one experiment. It means the company should maintain a reasonable, explainable connection between the expenditure and qualifying R&D.
How Plio helps organise this evidence
Plio helps businesses document R&D activities and prepare technical evidence without requiring them to replace their existing operational systems.
Lister AI assists with evaluating technical explanations, comparing them with published scientific and technological research and highlighting missing evidence.
Businesses can use Plio to organise R&D claim information alongside records from their existing project management and accounting software.
For more detailed industry-specific examples, explore the 13 R&D Tax Relief Case Studies.
Official HMRC references
- HMRC — Meaning of R&D for tax purposes
- HMRC — Expectations of R&D claimants
- HMRC — Additional Information Form requirements
All examples are fictional and do not establish eligibility.
Published by: Plio — Paylists LTD
Prepared and reviewed by: Muly Zohar, Founder & Product Architect
Last published:
Sources: Official HMRC guidance and other references linked in this article.
General information only. Plio is not a tax advisory service. Read about our content responsibility and review