R&D tax relief, prepared to withstand HMRC scrutiny
We prepare claims under the merged R&D scheme and ERIS, and we defend them if HMRC asks questions. R&D tax relief is all we do.
Every claim we prepare is built to be read closely: the technical narrative, the qualifying cost schedules and the return entries, prepared by a regulated chartered practice and signed off by a chartered adviser.
What the merged scheme’s 20% expenditure credit is worth per £1 of qualifying spend, net of corporation tax at 25%. It is 16.2% at the 19% rate, or where the company is loss-making
15%
What a loss-making, R&D-intensive SME receives in cash per £1 of qualifying spend under ERIS. The payable credit is not taxable
26.97%
The R&D intensity a loss-making SME must reach to claim ERIS, measured against total relevant expenditure, not the R&D alone
30%
Why companies trust us with their claims
Because we are accountable in ways many R&D agents are not. The mis-selling era left companies facing enquiries their advisers would not defend. Our answer is a regulated, chartered practice — and has been since 2017, under every version of the rules since.
Chartered on both fronts
A member firm of both the Chartered Institute of Taxation (CIOT) and ICAEW, led by a dual-qualified founder, with every claim signed off by a chartered adviser.
Regulated by ICAEW
Including anti-money-laundering supervision, with a published complaints route.
Bound by PCRT
Professional Conduct in Relation to Taxation governs every position we take.
Registered with HMRC
Registered with HMRC as a tax adviser, and named on every claim we prepare.
Enquiry support included
In every engagement as standard. If HMRC opens a compliance check, we handle the response.
We stand behind our work
We prepare the right claim, defensibly. Read about our regulation and standards.
Who we work with
Companies whose business is their R&D. Sector by sector, claims trip up in different places — each card names the complication we solve most often.
Life sciences
Grant stacks, CRO contracts and long pre-revenue phases.
→Biotech
Meeting the 30% intensity test while still pre-revenue.
→Medtech
Where regulatory and clinical work crosses the R&D boundary.
→Agritech
Field trials that seasons, sites and weather complicate.
→AI and robotics
Proving an advance in the field, not just a clever product.
→Space
Long programmes, grant funding and hardware that flies once.
→Aerospace and defence
Contracted programmes and who owns the claim.
→Cleantech and energy
First-of-a-kind plant and the prototype cost boundary.
→Software
Drawing the honest line on where software development qualifies.
→Engineering
Separating qualifying development from routine work.
→Manufacturing
Process trials on live production lines, costed defensibly.
→All sectors
Every sector we work in, including those not shown here.
→
How it works
Your fee is agreed before work starts, with no hidden costs. If we do not think you qualify, we say so.
01
Scoping call
A conversation about your work and your numbers. If we do not think you qualify, we say so.
02
Technical and financial workstreams
We interview your competent professionals, set the project boundaries and build the qualifying cost schedules.
03
Report and return
The technical report, the Additional Information Form and the return entries, prepared and filed by us as HMRC-registered agents.
04
Submission and aftercare
We submit, track progress with HMRC, and enquiry support is included as standard.
Our clients’ words
Hear from the R&D-performing companies we act for. More client feedback is on our testimonials page.
Sandy
Jellagen Limited
“We’ve worked with LimestoneGrey for several years and their professionalism, speed and clear approach make them a pleasure to work with. They quickly understand the complexities of our R&D and ensure the claims process is straightforward, fair and accurate.”
Dr Varghese
Laennec AI Limited
“Working with LimestoneGrey has been a genuinely positive experience. Their communication is clear and proactive and they are always on hand to answer queries and provide reassurance throughout the process. We have complete trust in their expertise and feel confident that our claims are being handled professionally.”
Marcus
Neurabotics Limited
“We have been very happy with the service provided by LimestoneGrey. In particular, their attention to detail has been exceptional, making the entire process smooth and reassuring for us.”
Recognition
Finalist, One Nucleus Awards 2026: Most Innovative Professional Services Company
Finalist, Finance Awards Wales 2026: Independent Practice of the Year
Business Wales Accelerated Growth Programme Gold Partner
Memberships and associations
We are members of, and work alongside, the innovation and life-sciences networks our clients operate in, across the UK.
Latest thinking
Technical analysis and firm news from the team, written by the advisers who prepare the claims.
Talk it through with a chartered adviser
A first conversation costs nothing and commits you to nothing. You will speak to a qualified adviser, not a salesperson.