Why HMRC Enquiry Rates Into R&D Claims Are Rising — And What It Means For You
A few years ago, an R&D tax credit claim landing on HMRC's desk was unlikely to attract a second look. That's no longer the world we operate in. If you've submitted a claim recently, or you're about to, you need to understand that the likelihood of receiving a compliance check letter is meaningfully higher than it was even two years ago — and the reasons behind that shift tell you a lot about what a strong claim needs to look like today.
What's changed
HMRC's R&D enquiry rate has risen sharply since 2022. The department has openly acknowledged that fraud and error in the R&D schemes were far higher than acceptable, and it responded by establishing a dedicated compliance team, expanding pre-claim checks, and adopting a far more sceptical starting position on every submission — not just those that look obviously wrong.
This isn't a temporary crackdown that will quietly ease off. It reflects a permanent recalibration of how HMRC treats R&D relief: as a valuable incentive that has been abused often enough that every claim now needs to prove itself, rather than being accepted on trust.
A few specific factors are driving the increase:
Volume-driven claims damaged trust in the system. The boom in specialist “R&D firms” offering fast, low-effort claims on a percentage-fee basis produced a wave of templated, poorly evidenced submissions. HMRC's response was blunt: assume more claims are wrong until proven otherwise.
The Additional Information Form raised the bar — and exposed the gaps. Since the AIF became mandatory, HMRC has far more visibility into the technical details (or lack thereof) behind a claim before it's even assessed. Thin or generic narratives that might once have passed quietly are now automatically flagged.
Digital cross-referencing has improved. HMRC increasingly compares claims against sector norms, company size, previous submissions, and other data points. Claims that look inconsistent with what HMRC would expect from a business of that type and size are more likely to be selected for review.
Political and media pressure hasn't gone away. R&D tax relief has been a recurring subject of scrutiny in Parliament and the press due to concerns about cost and abuse. That pressure keeps compliance resourcing and enquiry volumes elevated.
What this means for you
The practical consequence is simple: the standard of evidence and narrative quality that used to be “good enough” often isn't any more. A claim that would have sailed through in 2019 might now trigger questions — not because anything is fraudulent, but because the technical narrative doesn't clearly demonstrate the competent professional test, the resolution of genuine scientific or technological uncertainty, and the boundaries of what was and wasn't routine.
This matters whether or not you ever receive an enquiry letter. Claims are increasingly assessed on the assumption that HMRC might ask difficult questions later, so the narrative and evidence need to be built to withstand that scrutiny from the outset — not patched together defensively after the event.
It also means the choice of adviser matters more than before. A generalist accountant or a high-volume claims firm working from a template simply isn't positioned to write a defensible technical narrative for a genuinely complex engineering, software, or scientific project. HMRC's caseworkers can usually tell the difference between a narrative written by someone who understands the technical work and one generated from a standard framework.
How we approach this at Vantage
This is precisely why we built Vantage around engineering-led expertise rather than volume. John and Jason have real technical backgrounds across motorsport, automotive engineering, advanced manufacturing, and quantum technology — so when we write a technical narrative, it reflects an actual understanding of the uncertainty your team was working through, not a rephrased version of your project description.
And because our fee structure is a fixed base fee plus a modest success element, our incentive is to build a claim that holds up — not to process as many claims as possible as quickly as possible.
Rising enquiry rates aren't a reason to stop claiming R&D tax relief — the relief still exists for a good reason, and genuinely innovative UK businesses are entitled to it. But it is a reason to make sure your next claim is built to the standard HMRC now expects, with a technical narrative that a specialist, not a generalist, has put together.
R&D tax rules and HMRC's compliance approach continue to evolve, so this article shouldn't be treated as advice for your specific situation. Speak to a specialist adviser about your own claim.
Want a second opinion on your R&D claim before you submit it? Book a no-obligation call with John or Jason, or send us a brief overview of your projects for a free Loom video review.
