R&D tax relief UK — prove the advance, evidence the claim.
Research and development relief begins with a genuine scientific or technological problem—not a promise of a refund. Britvex helps UK companies organise the technical evidence, eligible expenditure and filing information needed to assess whether a defensible R&D Corporation Tax claim can be made.
Five connected checks
The claim must connect science, people, spend and Corporation Tax.
What HMRC tests is the underlying scientific or technological advance.
The purpose is not to label all innovation as R&D. It is to identify precisely what a competent professional in a relevant field could not readily achieve, where work to overcome that uncertainty began and where it ended.
More than a company-first feature
The work must seek an advance in overall scientific or technological knowledge or capability, not merely a feature that is new to the claimant. Improvements may qualify even if the final result is not commercially successful.
A problem experts cannot readily solve
Record why the solution was not readily deducible by a competent professional using available knowledge. The challenge must be technical, not simply budget, scheduling, market demand or product positioning.
Show what was actually attempted
Describe experiments, prototypes, modelling, tests, unsuccessful routes and modifications. The record should distinguish qualifying direct work and appropriate qualifying indirect activity from later routine delivery.
Explain who understands the field
The technical account should be supported by people with real expertise in the relevant science or technology. Identify the state of knowledge at the outset, why the uncertainty existed and how the company sought to resolve it.
Not every difficult project is a qualifying R&D project.
A well-run claim explains exclusions as clearly as inclusions. These common distinctions help prevent an ordinary delivery budget being treated as wholly qualifying expenditure.
Routine integration versus genuine uncertainty
Connecting standard APIs, deploying familiar platforms or upgrading interfaces is not automatically R&D. A novel technical limitation and experimental route may qualify, depending on the facts.
Commercial novelty is not enough
New design, better branding, wider product range or market differentiation may be valuable business activity without creating an advance in a field of science or technology.
Routine quality checks differ from resolving uncertainty
Normal quality assurance and compliance testing generally differ from tests whose purpose is to resolve scientific or technological uncertainty. Document when the uncertain technical work ceased.
Failure does not automatically disqualify work
Where qualifying uncertainty was genuinely addressed, unsuccessful trials can be relevant evidence. The aim, activity and time spent matter more than whether a saleable product was ultimately released.
Evidence → expenditure → claim.
A credible claim is assembled in stages. Each stage must connect to the same company, period, project and underlying records.
Confirm the relevant accounting periods.
Identify the claimant company, its Corporation Tax position, previous claims and whether the current or historical relief regimes apply. Establish notification and final-claim time limits before investing in detailed preparation.
Identify technological uncertainties.
Meet the technical leads, describe the field-wide advance sought, specify the uncertainties and document attempts to overcome them with contemporaneous evidence.
Check who commissioned the R&D.
Read client and subcontractor agreements, decide who planned and made the R&D decision, assess connected-party relationships and identify overseas activity. Contract labels alone can be insufficient.
Reconcile costs to the qualifying work.
Connect staff time, employers’ costs, relevant software, consumables, eligible data/cloud costs and externally provided worker or contractor charges to the qualifying activities.
Apply the appropriate relief scheme.
Distinguish the taxable merged expenditure credit from ERIS, check relevant loss-making and intensity conditions, caps and any special rules before estimating financial benefit.
Submit accurate evidence and tax forms.
Determine claim notification requirements, file the additional information form before the tax return claim, retain the technical account and align amounts with the CT600 and supporting Corporation Tax computation.
Merged RDEC and ERIS are distinct routes—not interchangeable percentages.
The figures below are legislation-linked headline rates for qualifying periods, not an individual savings estimate. Historical accounting periods beginning before 1 April 2024 can require different rules.
For accounting periods beginning on or after 1 April 2024, the merged RDEC-style expenditure credit is generally 20% of eligible expenditure. It is a taxable credit and passes through statutory allocation and payment stages; the effective benefit is not an unconditional 20% cash repayment.
Eligible loss-making R&D-intensive SMEs can claim an additional 86% deduction (186% enhanced expenditure in total). A payable credit at 14.5% of qualifying surrendered losses may be available, subject to rules and caps.
ERIS ordinarily requires relevant qualifying R&D expenditure of at least 30% of relevant total expenditure, taking connected companies into account. A one-year grace mechanism and detailed calculations may apply.
The accounting-period start date governs whether the previous SME/RDEC schemes or the reformed schemes are relevant. Never transfer a current headline rate backwards without checking the tax period and transitional rules.
Who decided the R&D should be undertaken—and where was it carried out?
Modern R&D rules turn heavily on commissioning, connected parties and geographical restrictions. A project may be eligible while specific contractor invoices are not, or vice versa.
Contracted-out research
Under the reformed schemes, check which company made the decision to undertake the R&D and planned it. Contracts, specifications, correspondence, payment responsibilities and project control can be material. A customer commissioning R&D and a software agency delivering it should not independently assume they both qualify for the same activity.
Externally provided workers
Distinguish workers supplied to the claimant from ordinary contractors. The rules for connected persons and expenditure proportions can differ. The company must identify who directs the worker, how their costs are evidenced and whether any relevant overseas limitations apply.
Overseas restrictions
Overseas subcontracted and externally provided worker costs are generally restricted under the reformed rules, with limited exceptions where the particular geographical, environmental, social, legal or regulatory conditions make performance abroad necessary. Lower cost or convenience is not by itself a sufficient exception.
Subsidies, grants and Northern Ireland
Funding can affect contracts and which entity bears the cost. Under the reformed merged scheme some older SME restrictions no longer apply in the same way, but the correct claimant still matters. Northern Ireland companies and certain subsidised activities can face special considerations; these are assessed case by case.
The cost schedule should trace every amount back to activity and source records.
A claim can fail on cost analysis even when the project itself qualifies. Keep eligibility, apportionment, timing, VAT treatment, accounting and related-party positions clearly documented.
Relevant salaries, employer NIC and pension costs may qualify to the extent they relate to eligible activities. Support proportions through credible time and responsibility records.
Identify qualifying worker arrangements and the permitted proportion of eligible charges, considering whether suppliers are connected and where the work was undertaken.
Document the contract, commissioning decision, underlying activities, connected-party status and permitted expenditure basis. Not every development invoice should be treated as qualifying.
Eligible consumable items and relevant software, data and cloud costs can qualify under the applicable conditions. Allocate shared costs on a supportable basis and exclude capital items or unrelated business expenses where not permitted.
R&D relief does not generally make capital expenditure, market research, commercial launches, patent fees or ordinary marketing automatically eligible. Separate these from eligible revenue expenditure and consider other tax treatments if relevant.
Evidence that a technical reviewer and an HMRC reviewer can follow.
A robust technical narrative is useful only when it can be reconciled to dates, people, invoices and project decisions. Retain a defensible audit trail even when the detailed technical work was outsourced.
What knowledge, tools and solutions were available before work began?
Who identified the uncertainty and why could it not be readily resolved?
When did qualifying activity begin, evolve and stop?
Dated tests, alternatives, prototypes, reports and significant decisions.
Payroll, timesheets, supplier invoices, ledger codes and allocation workings.
Who decided to undertake the R&D and who controlled the underlying work?
Accounting period, CT600, computations and prior R&D claims.
Claim notification (where needed), AIF submission and filing confirmations.
Two forms, one tax return—and deadlines that are not interchangeable.
The pre-claim filing process is a frequent source of invalid claims. Map all dates to the correct accounting period and distinguish an earlier notification from the eventual Corporation Tax claim.
Claim notification form
Where required—for example, first-time claims or claims outside the permitted previous-claim history—the company must notify HMRC within six months after the end of the relevant period of account. In some cases a company with earlier R&D claims must still notify because an exception applies. A late or missing required notification can invalidate a claim.
Additional information form (AIF)
All relevant R&D claims must have a supporting additional information form submitted before the claim is made on the Company Tax Return. The form sets out projects, technical uncertainty, qualifying costs and associated adviser/company details. Filing a CT600 first does not substitute for the required AIF.
Company Tax Return claim
The R&D claim and computation must agree with the Company Tax Return for the relevant accounting period, and the normal R&D claim time limit is generally two years after the end of that period. The statutory notice and return requirements must be applied to the actual facts.
Later enquiries and revisions
HMRC may ask for technical evidence, costs and explanations after submission. Keep the exact information used to support the claim, identify who is authorised to correspond and respond factually rather than relying on broad promotional labels.
Keep research expenditure connected to the company accounts.
R&D is a Corporation Tax issue, not a standalone marketing product. These existing Britvex services support the accounting and reporting framework.
Clear scope. Professional records. Connected support.
Britvex works within a defined engagement and its current regulatory position. We distinguish financial information, specialist tax review and decisions that require external legal or regulated professional advice.
Check the source, not just the summary.
The position can depend on the relevant tax year, accounting period, facts and later legislation. These official sources underpin the general explanations above.
- Qualifying project test — HMRC / GOV.UK
- Merged scheme and ERIS — HMRC / GOV.UK
- Eligible R&D expenditure — HMRC / GOV.UK
- Claim notification — HMRC / GOV.UK
- Additional information form — HMRC / GOV.UK
Material is general information and not a substitute for advice on your own circumstances. Regulatory material last reviewed 29 October 2026.
Questions worth answering before you act.
These practical answers explain general UK rules and what information is needed for a proper review. Specific legal and tax outcomes depend on the period, facts and current HMRC guidance.
What qualifies as R&D for UK tax relief?
A qualifying project must seek an advance in a field of science or technology and resolve scientific or technological uncertainty that a competent professional could not readily overcome using publicly available knowledge. Ordinary development or commercial novelty alone is not sufficient.
Can a software company claim R&D tax relief?
Possibly. Software work must involve an advance in computer science or technology, such as overcoming a genuine technological uncertainty. Routine integrations, configuration, user-interface improvements or copying known approaches are not automatically qualifying.
Is the merged R&D credit worth 20%?
For accounting periods beginning on or after 1 April 2024, the merged scheme provides a taxable expenditure credit calculated at 20% of qualifying expenditure. The net benefit depends on corporation tax and the statutory credit-payment steps; 20% is not a guaranteed net cash refund.
Is the 186% deduction available to every company?
No. The additional 86% deduction, giving 186% enhanced expenditure, is part of ERIS for eligible loss-making R&D-intensive SMEs. It is not the merged-scheme calculation for all claimants.
What does R&D-intensive mean for ERIS?
For relevant accounting periods, the normal threshold is at least 30% qualifying R&D expenditure relative to the relevant total expenditure of the company and connected companies, subject to detailed statutory rules and a possible one-year grace period.
Do I need to send HMRC a claim notification form?
A first-time claimant, and certain companies whose previous claim is outside the three-year lookback or falls into an exception, must notify HMRC within six months after the end of the relevant period of account. Missing a mandatory notification can invalidate the later claim.
Is the additional information form compulsory?
Yes. An additional information form is required for claims under the current R&D regime, and it must be submitted before the relevant Company Tax Return claim. It sets out project and expenditure information and includes named company and adviser details.
What is the deadline to make an R&D claim?
Claims generally must be made within two years after the end of the accounting period, subject to applicable rules. This is separate from any earlier six-month claim notification deadline and from Corporation Tax filing deadlines.
Can subcontracted development costs qualify?
Sometimes. For the reformed schemes the party that decided the R&D should be undertaken and planned it may be entitled to claim, but contractual facts, connected-party rules and qualifying-cost percentages matter. Both sides should not assume they can claim the same R&D.
Can overseas R&D expenditure qualify?
There are important limits for overseas externally provided workers and subcontracted R&D, with narrow exceptions where qualifying conditions make the work necessary outside the UK. A foreign supplier invoice is not automatically eligible.
Can we claim if a project failed?
A commercially unsuccessful project may still qualify if there was a genuine scientific or technological advance sought, real uncertainty and qualifying activities. Eligibility is not conditional on successful product launch.
Can we claim for marketing, design or routine testing?
Not simply because an expense relates to a new product. Commercial market research, aesthetic design, routine quality assurance and work after the uncertainty is resolved generally need to be separated from qualifying technical activities.
What evidence should a company keep?
Keep dated technical notes, the competent professional’s explanations, design alternatives, failed tests, project timelines, time allocation, payroll, contracts, invoices and cost reconciliations. Records should explain how claimed expenditure connects to resolving specific uncertainties.
Will HMRC accept a claim prepared by Britvex?
HMRC decides whether a claim is valid and whether expenditure is allowable. Britvex cannot guarantee acceptance, relief or the outcome of an enquiry; our role is to support accurate assessment, records and tax-filing work within an agreed scope.
Bring the facts. We’ll define the next professional step.
Contact Britvex about R&D claim eligibility. We confirm the work required, the records to supply and the agreed scope before undertaking client services. We do not guarantee a tax result, authority decision or filing outcome.
United Kingdom · International clients
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