Every so often we meet a company that has done everything right. The technical work is genuinely innovative, the costs are well documented, the narrative is strong — and then we find out they can’t claim. Not because HMRC rejected the claim. Because nobody told HMRC it was coming.
That’s the claim notification form, and it’s caught out more companies than almost any other change to the R&D tax relief scheme in recent years. If your accounting period began on or after 1 April 2023, and you haven’t previously claimed R&D tax relief or haven’t done so in the past three years, you now must notify HMRC formally before you can submit a claim. Miss the window, and the relief simply isn’t available for that period — regardless of how strong the underlying claim would have been.
Who actually needs to notify
You need to submit a claim notification form if you’re claiming R&D tax relief for the first time, or if you haven’t made a valid claim in the three years immediately before the notification deadline. If you’ve claimed within that three-year window, you’re generally exempt and can submit your claim as usual.
It’s an easy rule to underestimate. We’ve seen well-established companies caught out simply because a gap opened between claims — a change of adviser, a quiet year, or a claim that slipped past the deadline — without anyone realising that the gap had switched the notification requirement back on.
The deadline is tighter than people expect
The notification form has to be submitted within six months of the end of the relevant accounting period. For a company with a 31 December year end, that’s 30 June. For a 31 March year end, it’s 30 September. There’s no leeway and no appeal process for a missed deadline — HMRC’s position is straightforward: no notification, no claim, full stop.
What makes this genuinely risky is timing. Six months after your year end is often well before your accounts are finalised, and even earlier than your R&D tax adviser has scoped the claim. It can be before anyone in the business has properly reviewed which projects qualify. It’s easy for the deadline to pass quietly while everyone’s attention is on year-end accounts and Corporation Tax filings.
What the form requires
The notification itself is relatively short — company details, the accounting period, a high-level summary of the planned R&D activities, and the name of the main senior internal contact for the claim. It must be submitted by someone within the company or an authorised agent; it can’t be submitted by a third party who isn’t formally acting for you. It’s a lighter-touch submission than the claim itself, but it still needs to accurately describe the work and requires someone who understands both the R&D and the deadline to submit it.
Why this trips up good businesses
In our experience, it’s rarely the disorganised companies that get caught out — it’s the ones running lean, with a general accountant handling Corporation Tax and no dedicated R&D adviser tracking the calendar. General practice accountants are excellent at what they do, but pre-notification isn’t a mainstream Corporation Tax deadline, and it isn’t always top of mind six months after a year end, which can feel a long way from the claim itself.
This is exactly the kind of thing an engineering-led R&D adviser should be watching for you. When we take on a client, we set up tracking of the notification deadline against their accounting period — not something we scramble to remember when a claim is nearly ready. It’s a small administrative step with unforgiving consequences, and it deserves the same discipline as the technical narrative itself.
If you’re not certain whether your business needs to notify this year — or when your deadline falls — it’s worth checking now rather than finding out in month seven.
Get it checked before the window closes
Book a no-obligation call with John or Jason, and we’ll tell you plainly whether you need to notify and by when: www.vantagernd.co.uk/book-appointment
Prefer to start lighter? Send us a brief overview of your projects for a free Loom video review: www.vantagernd.co.uk/review-your-project
R&D tax relief rules can and do change. This article reflects our understanding of the current rules and isn’t a substitute for advice on your specific situation — please speak to another qualified adviser or us before acting.