The decision, stated plainly
Two routes, and this page won't tell you which one is yours
A client mentions a project that sounds like it might qualify for R&D relief. You've got two honest options. Handle it in-house: prepare the technical narrative, identify the qualifying costs, file the claim through the Company Tax Return, and own the client's HMRC risk on that piece of work going forward. Or refer it to a specialist adviser: give up that fee, keep the client relationship, and let someone whose day job is R&D claims carry the compliance and enquiry risk instead. Both are legitimate. What's changed recently is that the in-house route now comes with a formal obligation attached to it that didn't exist before.
What's actually new
Interacting with HMRC on a client's R&D claim is now a registration matter, not just a competence one
Advisers who interact with HMRC on a client's behalf now fall under a formal registration requirement under the Finance Act 2026, Part 7 (Schedule 20 sets out the exemptions to it, not the requirement itself). It isn't specific to R&D (it applies to tax-agent work generally), but it's directly relevant to this decision because R&D is exactly the kind of work a general practice tends to pick up as a bolt-on rather than a core service. If you're already registered and this is a normal part of what you do, nothing here changes. If R&D claims are an occasional, one-off thing your practice does for a client who asked, this is the moment to check what taking that on formally now involves, rather than assume the old informal arrangement still applies unchanged.
Where this actually bites: the registration requirement doesn't care how big or small the piece of work is. A practice that prepares one R&D claim a year for a long-standing client takes on the same obligation as a firm doing it at volume. That asymmetry is worth sitting with before deciding. It changes the maths on whether it's worth keeping in-house at all.
The case for handling it yourself
You already know the client, the accounts, and the business
Nobody outside your firm understands this client's numbers, history and trading pattern as well as you do. That's a genuine advantage when it comes to spotting whether a project has qualifying substance in the first place, before any specialist ever gets involved. If your practice already writes confident, specific technical narratives, understands the cost identification exercise, and is comfortable owning an HMRC enquiry if one comes, the registration requirement is a compliance step to complete, not a reason to stop. See R&D claim services for what preparing a claim actually involves, and the Additional Information Form guidance for what HMRC now requires on every claim.
The case for referring it out
The fee is smaller than the relationship, and the risk sits outside your normal competence
General tax and accounts competence and R&D technical-narrative writing are different skills. Describing a genuine technical uncertainty in a way that survives HMRC scrutiny is closer to a specialist writing exercise than a tax computation, and it's the part of a claim that most often decides whether it holds up. Referring a client to a specialist doesn't have to mean losing them: most published introducer arrangements are built so the accountant keeps the relationship and picks up a share of the adviser's fee instead of preparing the claim directly. See how to refer a client's R&D claim for how that actually works in practice, and who typically stays the client's main point of contact.
Decision helper
Alternatives and limitations
This page is the starting point for the decision, not the answer to it; that depends on what your practice already looks like. If you currently do R&D work in-house and the question is whether the new registration requirement changes that, go to should you stop doing R&D in-house. If you've already decided to refer and want the mechanics, go straight to how to refer a client's R&D claim. And if a client hasn't asked yet but you want to understand what R&D relief actually covers before they do, see R&D Tax Relief.
