No. There is no minimum R&D spend, and there has not been one for well over a decade: the £10,000 minimum expenditure requirement was removed for accounting periods ending on or after 1 April 2012. A company with £8,000 of qualifying expenditure can claim on it, and the relief is worked out exactly as it is for a company with £800,000.
The question usually comes from somewhere else. Plenty of advisers set a minimum of their own, declining claims below a certain size because their fee model does not work at that level. That is a commercial policy rather than a rule of tax law, and it is worth knowing which of the two you are being told when someone says your spend is too small.
A small claim carries the same obligations
Size changes the numbers, not the process. A first-time claimant still has to deal with claim notification, and missing that window invalidates the claim however small it is. Every claim needs an Additional Information Form, with project descriptions written to the same standard whether the qualifying spend is £5,000 or £5m. The costs still have to be identified against the statutory categories, the competent professional still has to explain the uncertainty, and the records still have to stand up: HMRC checked around one in six claims in 2023-24, its latest published figure, and a small claim is not exempt from that.
One thing does scale in your favour. The PAYE cap starts at £20,000 plus 300% of relevant PAYE and NIC, so a modest payable credit is rarely restricted by it. Small claims are seldom lost to the cap. They are lost to notification deadlines and to narratives written too thinly to defend.
The real question is whether it is worth preparing
At merged scheme rates, £10,000 of qualifying spend is worth somewhere around £1,500 to £1,620 net, depending on your tax position — the full arithmetic is here. Set that against what a defensible claim takes: identifying the qualifying activity, apportioning time honestly, drafting a narrative that survives a check, and being ready to answer for all of it if HMRC asks. Some small claims do not clear that bar, and we will say so rather than take the fee.
A cheap claim prepared badly is worse than no claim at all. It carries the same exposure as a large one and offers less to defend. HMRC enquiry support is included as standard in our fees, which is a reason to prepare a claim properly at the outset, not a reason to file a marginal one.
Timing is the part companies most often get wrong. If this year’s spend is small but a larger programme is starting, the notification requirement is worth checking now rather than in eighteen months, because the deadline is fixed by your accounting period and not by when you get round to thinking about the claim.
Where to go next
If you are unsure whether your spend justifies a claim, send us the rough numbers and a description of the work. We will tell you honestly whether it is worth preparing, including when the answer is no. The claim value calculator will give you an indication in the meantime.
Written by Matthew Jones ACA CTA. Last reviewed July 2026.
Sources
- CIRD81600: minimum expenditure — the £10,000 minimum and its removal for accounting periods ending on or after 1 April 2012.
- Work out your research and development tax relief — HMRC’s guidance on calculating a claim, whatever its size.
This page describes the rules as they stood at the review date above, as general information rather than advice on your circumstances. For how that distinction works, see our terms; for an answer on your own facts, talk to us.