Prepare an R&D tax credit claim
Organise R&D-eligible expenditure through the year so the year-end claim summary for your adviser is straightforward. Uses today's projects, expenses and payroll surfaces in YionStack. A dedicated R&D claim helper (OSG-34) is on the roadmap; this is how to do it cleanly today.
In this guide
Accounting- Steps
- 6
- Prereqs
- 3
- Pitfalls
- 4 common ones
- Related
- 3 guides
Walkthrough only — no setup wizard. The flow is exactly what you do inside YionStack today.
Before you start
- A list of projects where you have resolved (or attempted to resolve) genuine scientific or technological uncertainty — the HMRC R&D test, see /learn/rd-tax-credits-uk.
- Time tracking enabled in the projects module so staff R&D hours are recorded as you go.
- A tax adviser who will write the technical narrative and file the claim against the CT600. YionStack does not file the claim itself.
Steps
- 1
Mark each R&D project
In Projects, add a "R&D" tag to every project that meets the HMRC R&D test — there is a technical or scientific uncertainty, and a competent professional could not easily find the answer. Be honest with the test; a generous tag now is an expensive correction later if HMRC enquires.
- 2
Track staff time against R&D projects
Every staff member working on an R&D project logs their hours against that project in the time-tracking module. At year-end, the R&D apportionment of each person's salary is hours-on-R&D-project / total-paid-hours — derived from the timesheets and the payroll runs, no manual estimation needed.
- 3
Tag subcontractor and EPW invoices
When booking a bill from a subcontractor or externally provided worker that worked on an R&D project, link the bill to the project (in the bill's project picker). The bill's value (subject to HMRC's subcontractor restriction rules — typically 65% of cost for unconnected subcontractors) becomes claimable R&D expenditure on that project.
- 4
Label R&D software, cloud and consumables
Recurring software subscriptions used directly in R&D (cloud compute, scientific software, prototyping tools) post as expenses tagged to the relevant R&D project. Same for consumables and EPW data services. Keep the apportionment evidence-based — if it is 70% R&D, post 70%.
- 5
Generate the year-end summary
At year-end, run a project P&L report filtered to R&D-tagged projects. The output — qualifying expenditure by category (staff costs, subcontractors, EPWs, software, consumables) per project — is exactly what your adviser needs to fill in HMRC's Additional Information Form. Export as CSV + PDF and hand it across.
- 6
Capture the technical narrative as you go
On each R&D project, keep a project note describing the scientific or technological uncertainty you faced and the systematic attempts you made to resolve it. Written quarterly, this is straightforward; written at year-end from memory, it is painful. The narrative is what HMRC reads to assess the claim's validity.
Common pitfalls
Under-claiming staff time
Directors and senior engineers regularly under-report their R&D time because they think the meetings, code review and design discussions do not count. They do. Anything that is part of resolving the uncertainty counts — log it.
Forgetting routine subcontractor invoices
Subcontractor work — even routine pieces like specialist testing, a CAD drafting hour, a software consultant — counts if it contributed to the R&D project. The 65% subcontractor restriction reduces the claimable amount but does not zero it. Tag the bill at booking time, not at year-end.
Tagging projects that do not meet the HMRC test
A project that delivered a normal commercial outcome with off-the-shelf tools is not R&D, even if it was hard. The test is the technological uncertainty a competent professional could not easily resolve, not the difficulty of the work. An adviser will refuse to claim on a borderline tag; better to tag conservatively.
Treating YionStack as the filer
YionStack organises the data. It does not file the R&D claim — that attaches to the CT600 corporation tax return and the technical narrative + Additional Information Form is the adviser's domain. The dedicated R&D claim helper (OSG-34) on the roadmap will produce a more structured handover; today it is project P&L + your notes.
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