The merged scheme and ERIS, explained
For accounting periods beginning on or after 1 April 2024, the old SME and RDEC schemes are replaced by two routes: the merged expenditure-credit scheme and Enhanced R&D Intensive Support (ERIS). This page explains both in HMRC's published terms - and one thing up front: which route applies to your company is your accountant or adviser's determination. Aven does not select your scheme.
The two routes, in HMRC’s published terms
The merged scheme
An above-the-line R&D expenditure credit with a headline rate of 20% of qualifying expenditure. The credit is itself taxable as trading income, so the net cash benefit works out lower - roughly 15-16.2% depending on your tax position. (The 20% is HMRC’s published rate; the net range is arithmetic, not a separate published figure.) It is the general route for periods beginning on or after 1 April 2024, replacing both the old SME scheme and RDEC.
ERIS
Enhanced R&D Intensive Support applies, in HMRC’s terms, to loss-making SMEswhose qualifying R&D is at least 30%of total expenditure. It gives an extra 86% deduction (186% total) and a payable credit of up to 14.5% of the surrenderable loss - HMRC frames it as “up to £27 per £100” of R&D, a ceiling rather than a guarantee.
Who decides which route applies
Not Aven. Whether your company meets the SME conditions, whether it is loss-making for these purposes, whether the 30% intensity condition is met, and how any claim interacts with your wider tax position are determinations for your accountant or R&D tax adviser - they involve your accounts, your group structure and your filing strategy, none of which Aven advises on.
The boundary, plainly:Aven does not select your scheme, determine your liability, or sequence loss relief. Aven builds the evidence pack - the narratives, the linked record trail and a conservative cost model - and your accountant or R&D tax firm decides the scheme and files the claim.
What both routes have in common: the evidence
Whichever route your adviser determines, the substantiation is the same shape. The work must meet the advance and uncertainty tests. Every claim needs the mandatory Additional Information Form with project-by-project narratives and a cost breakdown. And if HMRC opens a compliance check, it asks for contemporaneous records behind the narratives. That common core is what Aven assembles - a scheme-agnostic, AIF-aligned evidence pack your adviser can rely on under either route. For the wider regime - deadlines, qualifying costs and restrictions - see R&D tax relief explained
Common questions
Which scheme applies to my company?
That is a determination for your accountant or R&D tax adviser, not for Aven. In HMRC's published terms, the merged scheme is the general route for periods beginning on or after 1 April 2024, and ERIS is available only to loss-making SMEs whose qualifying R&D is at least 30% of total expenditure - but applying those conditions to your company's facts is your adviser's job.
What is the merged scheme rate?
HMRC's published headline rate is a 20% expenditure credit on qualifying R&D spend. The credit is itself taxable, so the net cash benefit works out lower - roughly 15-16.2% depending on your tax position. The 20% is the published rate; the net range is arithmetic, not a separate published figure.
What does ERIS give, and who is it for?
Enhanced R&D Intensive Support is for loss-making SMEs whose qualifying R&D is at least 30% of total expenditure. It gives an extra 86% deduction (186% total) and a payable credit of up to 14.5% of the surrenderable loss - HMRC frames it as up to £27 per £100 of R&D, a ceiling rather than a guarantee.
Does the evidence differ between the two schemes?
The substantiation burden is the same shape either way: the mandatory Additional Information Form, project narratives covering the advance and uncertainty, a qualifying cost breakdown, and contemporaneous records if HMRC checks the claim. That is why Aven builds one scheme-agnostic evidence pack and leaves scheme selection to your adviser.
Aven assembles R&D evidence packs for accountant review; Aven Reviewed adds expert review. Aven does not file with HMRC, determine your liability, select your scheme (merged vs ERIS), sequence loss relief, or guarantee any amount - those are your accountant or R&D tax firm's responsibility. Figures are indicative and conservative. Nothing here is tax advice. UK only.
The scheme is your adviser's call. The evidence is ours.
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