Research and Development (R&D) tax reliefs
UK companies carrying out qualifying research and development (R&D) projects may be able to claim Corporation Tax relief or a payable tax credit through HM Revenue & Customs' (HMRC) R&D tax relief schemes.
What qualifies as R&D
For tax purposes, R&D work must aim to achieve an advance in science or technology and involve overcoming scientific or technological uncertainty. Projects can include developing or improving:
- products
- processes
- services
- software
Work in the arts, humanities, or social sciences does not qualify. The R&D must relate to the company’s existing trade or a trade the company intends to start based on the R&D results. You can use the HMRC's tool to find out if your project involves R&D for tax purposes.
More guidance is available to help you understand:
- the meaning of R&D for tax purposes
- the definition of R&D for tax purposes
- if your work qualifies as R&D for tax purposes
Current schemes (for accounting periods beginning on or after 1 April 2024)
Merged R&D expenditure credit scheme (RDEC)
Most companies claiming R&D relief claim under the merged R&D expenditure credit scheme. The scheme is available to companies of any size carrying out qualifying R&D activities.
Enhanced R&D Intensive Support (ERIS)
Additional support is available for certain loss-making R&D-intensive small and medium-sized enterprises (SMEs). To qualify, a company must:
- meet the SME size conditions
- be loss-making for tax purposes
- meet the R&D intensity requirements set by HMRC
Find out if you can claim under the merged RDEC scheme or ERIS scheme for accounting periods beginning on or after 1 April 2024.
ERIS for loss-making SMEs based in Northern Ireland
There are specific provisions for loss‑making, R&D‑intensive SMEs with a registered office in Northern Ireland. These affect how ERIS and overseas expenditure limits apply. Certain businesses can choose to opt out of these provisions. Find out more about ERIS for loss-making SMEs based in Northern Ireland.
Older accounting periods (beginning before 1 April 2024)
For accounting periods beginning before 1 April 2024:
- SMEs generally claim under the SME R&D tax relief scheme
- larger companies generally claim under the legacy RDEC scheme
Different rules may still apply when amending or reviewing earlier claims. Check if you need to submit a claim notification form before you claim R&D Corporation Tax relief.
Advance assurance for R&D tax relief claims
HMRC offers advance assurance services to help businesses get certainty about certain aspects of their R&D tax relief claims before they submit them. This can be useful if you are unsure whether your project or costs qualify. You can apply for:
- targeted advance assurance, which gives a view on specific aspects of a claim (pilot running for 12 months from 18 May 2026)
- full claim advance assurance, which applies to an entire claim (usually for first-time claimants)
You cannot apply for both services for the same claim. Check if you can apply for advance assurance for your R&D tax relief claim.
Before making an R&D tax relief claim
Depending on the accounting period and circumstances, you may need to:
- tell HMRC that you're planning to claim R&D tax relief
- submit an additional information form to support the claim
Claims are made through the Company Tax Return. For more information, see HMRC's collection of guides on R&D tax relief.
Correcting past claims
HMRC provides an R&D disclosure facility for companies that need to correct mistakes in earlier R&D tax claims. This is for non-deliberate errors only. You can use this facility to pay back overclaimed tax credits or any extra Corporation Tax you owe. You should only use this if you are out of time (usually more than 12 months past the filing deadline) to amend your tax return. Find out more about the HMRC's R&D disclosure service.
