Every growing engineering or technology business eventually reaches the same crossroads: R&D activity is increasing, the relief is significant, and someone in finance asks the obvious question — should we build this capability internally or bring in a specialist? There’s no single right answer. But there is a wrong way to make the decision, and that’s guessing. Here’s how to think it through.
Why some businesses build the capability in-house
For a handful of larger, well-resourced companies, an in-house R&D tax function makes sense. If you’re submitting substantial claims every year, have a finance team with genuine capacity, and can dedicate someone to staying current with HMRC guidance as it evolves, doing it yourself is a legitimate option. You retain full control of the process, and over time the internal team develops institutional knowledge of your projects that’s hard for any outside adviser to match immediately.
The businesses that do this well tend to share three things: a stable finance function that isn’t already stretched thin, technical staff willing to invest real time in writing narratives (not just answering a few questions), and someone senior enough to own the risk if HMRC opens an enquiry.
What doing it properly in-house actually requires
This is where most businesses underestimate the commitment. A defensible R&D claim isn’t a form-filling exercise — it’s about translating genuinely technical work into a narrative that meets HMRC’s definition of a “competent professional” advancing science or technology, while accurately apportioning qualifying costs among staff, subcontractors, software, and consumables. Doing this well in-house means someone needs to:
- Understand the current eligibility rules in detail, including how the merged scheme and the Additional Information Form have changed HMRC’s expectations since 2023
- Interview technical staff and translate engineering or R&D work into language that withstands scrutiny — without overstating or underselling it
- Keep pace with a rapidly shifting compliance environment; HMRC enquiry rates have risen sharply, and the bar for what counts as an adequate technical narrative keeps rising
- Use professional judgement to know where a project’s claim is strong and where it’s genuinely borderline
None of that is impossible to build internally. But it takes real time away from the people doing the R&D, and if HMRC opens an enquiry, the business is defending its own work without an independent perspective to draw on.
When outsourcing makes more sense
For most SMEs, outsourcing to a specialist adviser is the more efficient option — not because the work is too hard, but because it isn’t your core business. A few signs it’s the right call for your business:
Your technical team’s time is better spent on the work itself. Every hour an engineer spends writing a claim narrative is an hour not spent on the R&D that produced it in the first place.
You’ve had a claim challenged, reduced, or rejected before. That’s usually a sign the technical narrative wasn’t robust enough, not that the underlying work wasn’t qualifying activity.
Nobody internally has the capacity to track HMRC’s evolving expectations. The rules, forms, and levels of scrutiny have all changed materially over the past three years, and staying current is a specialism.
Your R&D spans genuinely complex or niche technical territory. Motorsport, advanced manufacturing, quantum technology, aerospace, defence — areas where a generalist accountant, however competent, may lack the depth to build the strongest possible case.
A hybrid approach is often the right one
In practice, the businesses that get the most value tend to combine the two: their own technical staff remain the source of detail, while a specialist adviser handles the framing, cost apportionment, HMRC-facing documentation, and enquiry defence if it’s ever needed. This keeps the burden off engineering time while ensuring the final claim is built by people who do this every day and know exactly what HMRC is looking for.
Our view
We built Vantage specifically for this middle ground. Because John and Jason both have engineering backgrounds, we extract the technical detail directly from conversations with your team rather than handing them a template to fill in — which is usually where the burden of “doing it in-house” lies. We then build the narrative, apportion the costs, and stand behind the claim if HMRC asks questions later.
R&D tax rules continue to evolve, and the right approach for your business will depend on your specific circumstances — this isn’t a decision to make on general principle alone. If you’re considering whether to bring your R&D tax claim in-house or hand it to a specialist, we’re happy to talk it through.
Book a no-obligation call with John or Jason: www.vantagernd.co.uk/book
Alternatively, send us a brief overview of your projects for a free Loom video review: www.vantagernd.co.uk/review-your-project