Subsidised R&D tax relief in the UK: expert guide

If you’ve ever received a grant, contract payment, or external funding for your research and development work, you’ve likely encountered one of the most confusing aspects of UK tax relief: subsidised expenditure. 

However, a series of landmark tribunal cases and the introduction of the merged scheme (2024) have completely redefined the landscape, creating new opportunities and demanding a new approach to HMRC compliance check preparation. This guide explains the technical differences, the crucial legal precedents, and the game-changing changes coming into effect post-April 2024, ensuring your claim for subsidised R&D tax relief is both maximised and robust.

The legal definition of subsidy vs. commercial income

In HMRC terminology, “subsidised expenditure” refers to R&D project costs that are met, directly or indirectly, by another person, such as a grant provider, government body or commercial customer.

Subsidised expenditure, as defined in Section 1138 CTA 2009 (relevant for SME claims for accounting periods beginning before 1 April 2024), refers to R&D project costs met, directly or indirectly, by another person. Under the old SME rules this dictated scheme eligibility, forcing the use of the RDEC rules for those specific costs.

Critical distinction: subsidy vs. commercial contract payment

A subsidy is generally a payment clearly tied to the R&D cost, whereas commercial income is a payment for a final deliverable or service, which tribunals have ruled is generally not a subsidy.

The key issue that resulted in multiple tribunal cases was HMRC’s previous, restrictive interpretation that a standard payment received under a commercial contract was considered a subsidy. Taxpayers successfully challenged this view by arguing that a company carrying out R&D at its own risk, and for which the customer simply pays for a finished product or service, should not lose relief.

The key legal test established by recent rulings is this: A subsidy is generally a payment clearly tied to the R&D cost, often given without the funder receiving a clear, commercial return. Standard sales revenue for goods or services is usually not a subsidy because the payment is for the final, delivered output, not the internal R&D process used to achieve it.

Three categories of subsidised expenditure before the merged scheme

Before the merged scheme, subsidised expenditure was categorised as notified state aid (disqualified all SME relief), Grants/Subsidies not classed as state aid (partial RDEC claim), and Indirect Funding (commercial contracts).

1. Notified state aid: Funding formally classified as notified state aid meant that all expenditure on the related R&D project was entirely disqualified from the SME scheme. This was the “notified state aid trap.”
2. Grants and subsidies (Not State Aid): For funding not classified as State Aid (e.g., standard Innovate UK grants), the R&D expenditure was only subsidised to the extent of the grant amount.
3. Indirect funding: Payments otherwise met directly or indirectly by a third party (the focus of the commercial contract tribunal cases).

The impact of tribunal rulings and HMRC guidance updates

Following tribunal losses, HMRC revised its guidance to confirm that payment for a commercial contract does not automatically subsidise the R&D within it, shifting to a case-by-case factual assessment.

In February 2025, HMRC updated its guidance (specifically CIRD81650 and CIRD84250). The underlying legislation did not change, but the manuals now confirm that payment for undertaking a commercial contract does not automatically subsidise the R&D within it; instead, whether a subsidy exists depends on the specific facts and whether the payment is clearly linked to the R&D costs.

Which key tribunal cases reshaped the subsidised R&D rules?

Landmark cases like Quinn, Collins, and SOCS established that customer payments are for the final deliverable, not the internal R&D process, preventing R&D within commercial contracts from being automatically deemed subsidised.

Quinn (London) Ltd (2021)

This judgment determined there was no clear link between the price paid by the customer (for a completed construction project) and the expenditure on R&D (innovative construction techniques). The tribunal ruled that the payment was for the final deliverable, not the R&D process, meaning the R&D expenditure was not subsidised.

Collins Construction & SOCS (2024)

In both the Collins Construction Ltd and Stage One Creative Services Ltd (SOCS) cases, the tribunal reinforced the Quinn principle. They found no evidence linking customer payments specifically to the R&D costs, strengthening the view that R&D undertaken by a company at its own risk, even within a commercial contract, is not automatically subsidised.

What types of funding may subsidise your R&D?

Any funding source that directly contributes to the cost of your R&D project may trigger the subsidised expenditure rules (for pre-April 2024 claims). These include:

• Government grants: Innovate UK grants (like Smart Grants), SBRI contracts, and regional or devolved government funding.
• European funding: Funds received from EU programmes (e.g., Horizon Europe), subject to specific Post-Brexit Status and EU Rules.
• Commercial contracts and customer funding: Where a contract explicitly ties payment to the performance of specific R&D activities, this may be considered a subsidy.
• Shareholder and director funding: Generally, internal capital is not a subsidy unless it originates indirectly from a grant awarded to a connected party.

Key funding sources summary table

To help you quickly identify subsidy status, here’s a reference guide: Types of funding and their impact

Funding Type	Counts as Subsidy?	Impact on Claim	Example
Innovate UK Grant	Yes	RDEC or hybrid	£50K grant on £100K project
Commercial Contract	No (if incidental R&D)	Potential SME eligibility	Software development contract
Shareholder Loan	Generally no	No impact	Director’s £25K loan
Regional Dev. Grant	Yes	RDEC or hybrid	£30K council innovation fund
Customer Prepayment	Depends	Case-by-case	Quinn case scenario
Horizon Europe	Yes	RDEC or hybrid	€100K EU research grant

What was subsidised expenditure under the legacy SME scheme (Pre-April 2024)?

If you are filing a retrospective claim for an accounting period starting before 1 April 2024, the “Old Rules” apply. This required a strict segregation of costs.

Under the legacy system, you could not claim SME relief on subsidised expenditure r&d. Instead, you had to split your project:

• Unsubsidised Portion: Claimed under the generous R&D tax credit for SMEs.
• Subsidised Portion: Claimed under the less generous RDEC scheme.

How does subsidised R&D work under the merged scheme (post-1 April 2024)?

The key change: For accounting periods starting on or after 1 April 2024, the legal restriction relating to subsidised expenditure has been removed under the R&D merged scheme. This allows companies to claim R&D relief on the entirety of their qualifying expenditure under the new RDEC-based merged scheme, regardless of grant or subsidy funding.

The landscape of subsidised R&D has fundamentally changed with the introduction of the merged scheme (2024).

The new single scheme applies the RDEC mechanism (now 20% of qualifying expenditure) to virtually all claimant companies, regardless of size or previous subsidy status.

Benefits of simplified compliance

For accounting periods beginning on or after 1 April 2024, the removal of the subsidy restriction is a major simplification. Companies no longer need to complexly apportion costs or worry about the notified state aid trap or commercial contract complications. This leads to easier calculations and claim submissions.

• Simplified calculation: Companies no longer need to complexly apportion costs between the SME and RDEC regimes or worry about the notified state aid trap.
• Increased certainty: Companies receiving grants (such as from Innovate UK or SBRI) can now claim R&D relief on the entirety of their qualifying expenditure under the merged scheme, subject only to the standard RDEC rate.
• R&D Intensive Scheme (ERIS): Even loss-making R&D intensive SMEs claiming under the enhanced ERIS exception are now explicitly exempt from the subsidised expenditure rules, ensuring their higher relief rate is not compromised by grant funding.

Action plan for transitional claims and future funding

Proactive due diligence remains essential, requiring companies to verify the state aid classification and purpose of payment in any funding agreement to manage risk during the transitional period.

While the new merged scheme removes the restriction on claiming relief for subsidised costs, proactive management of funding sources remains crucial, especially for businesses with one accounting period beginning before and the next beginning on or after 1 April 2024.

Essential contractual due diligence for R&D funding

Key due diligence steps include checking if funding is classified as notified state aid and ensuring contracts clearly define whether the money is for R&D activity (subsidy risk) or for purchasing a finished output (commercial payment).

Before signing any grant or funding agreement, perform the following due diligence:

• State aid classification: Check the agreement to see if the grant provider classifies the funding as notified state aid.
• Purpose of payment: Ensure contracts clearly define whether the money is for:
  • R&D activity (subsidy risk): Where the money is given to undertake technical development work.
  • Purchasing a finished output (commercial payment): Where the money is paid for a functional deliverable, regardless of the R&D that went into its creation.

Navigating the R&D transition with expert support

The transition period, where some accounting periods are governed by the old, complex subsidised R&D rules and others by the new merged scheme, presents a high risk of error and subsequent HMRC compliance check. Navigating the historical complexity of indirect funding, hybrid claims, and the impact of the Quinn case ruling requires expert analysis.

Alexander Clifford can provide clear, compliant guidance through this transition, ensuring you correctly maximise your claim benefit while mitigating the risk of penalties.

R&D tax subsidised expenditure – FAQs

 

What is the difference between ‘subsidised expenditure’ and a normal commercial payment?

Historically, ‘subsidised expenditure’ referred to costs met by an external party where there was a clear and direct link between the funding and the R&D costs. A normal commercial payment, particularly after recent tribunal rulings (like Collins), is payment for a final product or service, where the R&D is internal and at the company’s risk, and thus is generally not considered a subsidy.

I received an Innovate UK grant. Does this mean I cannot claim SME R&D tax relief?

For accounting periods before 1 April 2024, if the Innovate UK grant was not notified state aid, you could claim the SME R&D tax relief on the unsubsidised portion of the expenditure. The portion covered by the grant was claimed under RDEC. If the grant was notified state aid, the entire project had to go through RDEC.

What happens to the subsidy rules under the new R&D Merged Scheme?

For accounting periods starting on or after 1 April 2024, the rules relating to subsidised expenditure have been removed. Companies can now claim R&D relief on 100% of their qualifying expenditure, even if it was grant-funded, under the single Merged Scheme (RDEC) rules.

How can I verify if my grant is classified as notified state aid?

You should review the official offer or funding letter from the grant provider. They must specify if the funding is provided under specific State Aid regulations, such as the General Block Exemption Regulation (GBER) or if it is explicitly notified state aid. If the classification is unclear, contact the funding body or seek specialist advice.

Can I amend an old R&D claim if I incorrectly restricted my costs due to a subsidy?

Yes, potentially. Following the HMRC guidance updates and the clarity provided by the tribunal cases (Quinn, Collins, SOCS), many companies who previously restricted their claims due to customer funding may now be entitled to amend those claims. This is only possible if the amendment window is still open in most cases this is around two years from the end of the relevant accounting period, although other routes may sometimes be available outside that window.