The history of the R&D tax credit scheme

The history of R&D tax credits starts in 2000, when the UK introduced a dedicated tax incentive to encourage companies to invest more in research and development. Over the last 25+ years, the scheme has expanded, been simplified, tightened, and reshaped to keep pace with how innovation happens in real businesses.
The history of R&D tax credits starts in 2000, when the UK introduced a dedicated tax incentive to encourage companies to invest more in research and development. Over the last 25+ years, the scheme has expanded, been simplified, tightened, and reshaped to keep pace with how innovation happens in real businesses.
Today, R&D tax relief remains a core part of the UK’s innovation toolkit. For accounting periods beginning on or after 1 April 2024, most companies now claim under the merged R&D tax relief scheme, with Enhanced R&D Intensive Support (ERIS) available for certain loss-making, R&D-intensive SMEs.
This relief can reduce Corporation Tax and, depending on a company’s circumstances and restrictions, can sometimes translate into a payable credit.
The history of R&D tax credits
R&D tax credits were first launched for SMEs in 2000 by the UK Government. After consultation, the incentive was introduced under the Labour government, with Chancellor Gordon Brown. The underlying idea was to encourage more private-sector R&D by reducing the cost of taking on scientific and technological uncertainty.
The incentive began as an enhanced deduction and, over time, evolved into two routes: one primarily for SMEs and one for larger companies, before later being brought back together through the merged scheme.
2002-2008
In April 2002, several important developments took place:
- R&D capital allowances were introduced to provide tax relief for certain R&D-related capital expenditure, replacing the old Scientific Research Allowances
- Changes to Corporation Tax rates for smaller companies were introduced in this era
- A separate form of R&D relief for large companies began to take shape, recognising that larger groups also needed a clear incentive to back risky innovation
In September 2003, the SME scheme was made more accessible with the removal of a minimum spend and the simplification of claiming for R&R-related staffing costs.
Further changes were introduced in April 2004, with a wider range of costs eligible to be claimed for, including those materials either consumed or transformed in the R&D process (such as water, fuel and power).
In 2008, the threshold for headcount, annual turnover and balance sheet assets were doubled under an amendment to SMEs, meaning more companies were classified as such and could claim under the scheme. At the same time, scheme relief rose from 50% to 75% (and increased again to 100% in 2011 and 125% in 2012) and payable credit dropped from 16% to 14% (to 12.5% in 2011 and 11% in 2012).
2009-2015
HMRC broaden the scope in 2009 by introducing Qualifying Indirect Activities (QIA), allowing more activities to be claimed for under the scheme, such as the admin, finance and security costs associated with R&D projects.
In 2011, the Corporation Tax rate for non-SMEs is reduced from 28% to 26% – this was to support the government’s goal whereby all companies have a single rate of Corporation Tax, dropping from 30% to 20% between 2002 and 2015.
April 2012 saw another reduction in Corporation Tax (26% to 24%), a change to the definition of EPW (Externally Provided Workers) which removed a restrictive set of requirements, as well as the removal of minimum spend and the PAYE and NIC liabilities cap.
In April 2013, the RDEC incentive (Research and Development Expenditure Credits) was introduced, replacing the large company scheme that was previously in effect. RDEC accounts for the benefit in profit-before-tax and was brought in to provide greater certainty, value and visibility to loss-making companies. Two years later, the RDEC rate increased from 10% to 11%.
In 2015, when the Corporation Tax finally became 20% for all companies, the SME scheme enhancement was increased to 130% and tighter rules were imposed on the eligibility of consumable materials.
2016-2022
In 2016, after 3 years of running side by side with RDEC, the large company super deduction scheme was terminated. Two years later, in 2018, the RDEC rate was increased to 12%.
2019 saw the introduction of an online service for SME and RDEC claims as well as the first consultation by the government to prevent the R&D tax relief scheme from being abused, including the reintroduction of the PAYE and NIC cap in 2021. Also in 2019, HMRC made CT600 and computation mandatory in a bit to improve the quality of tax credit claims.
2020 saw a further three consultations, including part two of Preventing Abuse of the R&D Tax Relief for SMEs, which meant businesses that had a payable tax credit of less than £20,000 did not need to apply the PAYE and NIC cap. The other two consultations focused on data and cloud computing expenditure and the UK Research and Development Roadmap. The RDEC rate is also increased this year, to 13%.
In 2021, the government responded to the R&D tax relief consultation and announced reforms: data and cloud costs were now included within qualifying expenditure, UK innovation was refocused and steps were taken to improve compliance and reduce system abuse. In response to the coronavirus pandemic, the government also allowed businesses to temporarily set losses against up to three previous profitable years.
2023 onwards
Looking ahead, April 2023 is set to include more allowances within qualifying expenditure (including data licenses, cloud costs and pure mathematics), and new measures will be introduced to further limit abuse of the R&D tax relief system.
The introduction of R&D tax credits saw the UK join several other countries such as Canada, Hungary, Japan and the United States that were already offering research and development tax credit incentives to drive innovation among businesses.
R&D tax relief was designed to encourage growth and reward businesses to invest in either new or improved products, processes, services, devices or systems.
Not only have R&D tax credits withstood the 2008 financial crisis as well as several government changes since their introduction, but they also remain an important element of business funding today.
To find out more, watch our helpful video.
SME vs. RDEC
Following the SME tax credit incentive, a separate incentive for larger enterprises called the R&D expenditure credit (RDEC) was later launched in 2002.
Both branches of the tax credit scheme allow small and larger businesses to invest in innovation and development:
- The SME (Small-Medium Enterprise) branch is designed for small to medium-sized businesses
- The Research and Development Enhanced Credit (RDEC) scheme is designed for larger corporations
SME tax credits are suitable for businesses that:
- Employ no more than 500 staff members
Have an annual turnover of under 100 million euros OR a balance sheet of under 86 million euros.
RDEC tax credits are suitable for businesses that:
- Employ over 500 staff members
- Have an annual turnover of 100 million euros or more
- Have at least 86 million euros in gross assets
Read more about the accounting treatment for R&D tax credits.
What are the benefits of R&D tax credits?
There are countless business benefits of R&D tax credits, including:
- A rebate on your Corporation Tax
- A payable tax credit or cash
- An enhanced deduction which your company can carry forward should you wish
- Improved cash flow
- Extension of funding
- Demonstrates to investors and stakeholders that you are developing something valuable in the eyes of the government
What counts as R&D?
R&D for tax purposes is defined by the UK Government as taking place when a project seeks an advance in science or technology. Despite misconceptions, this can apply to any sector.
This can include the development of a new:
- Product
- Process
- Service
- Device
- Knowledge
It also includes the improvement of any of the above. R&D qualifying activities can also look different depending on the sector that you operate in. You can also make a claim if a project was unsuccessful in reaching its goal.
FAQs


The history of R&D tax credits starts in 2000, when the UK introduced a dedicated tax incentive to encourage companies to invest more in research and development. Over the last 25+ years, the scheme has expanded, been simplified, tightened, and reshaped to keep pace with how innovation happens in real businesses.
The history of R&D tax credits starts in 2000, when the UK introduced a dedicated tax incentive to encourage companies to invest more in research and development. Over the last 25+ years, the scheme has expanded, been simplified, tightened, and reshaped to keep pace with how innovation happens in real businesses.
Today, R&D tax relief remains a core part of the UK’s innovation toolkit. For accounting periods beginning on or after 1 April 2024, most companies claim under the merged R&D tax relief scheme, with Enhanced R&D Intensive Support (ERIS) available for certain loss-making, R&D-intensive SMEs.
This relief can reduce Corporation Tax and, depending on a company’s circumstances and restrictions, can sometimes translate into a payable credit.
The history of R&D tax credits
R&D tax credits were first launched for SMEs in 2000 by the UK Government. After consultation, the incentive was introduced under the Labour government with Chancellor Gordon Brown. The underlying idea was to encourage more private-sector R&D by reducing the cost of taking on scientific and technological uncertainty.
The incentive began as an enhanced deduction and, over time, evolved into two routes: one primarily for SMEs and one for larger companies, before later being brought back together through the merged scheme.

2002-2008
2002
In April 2002, several important developments took place. R&D capital allowances were introduced to provide tax relief for certain R&D-related capital expenditure, replacing older approaches to scientific research allowances. In the same period, the large-company side of R&D relief began to take shape, recognising that bigger organisations also needed an incentive to back risky innovation.
2003
In September 2003, the SME scheme became more accessible. Changes removed barriers such as minimum spend requirements and simplified how R&D-related staffing costs could be claimed, making it easier for smaller companies to participate.
2004
Further changes were introduced in April 2004, widening the range of eligible costs. This included clearer recognition of consumables used up or transformed in the R&D process, such as certain materials, water, fuel and power when attributable to the R&D activity.
2008
In 2008, the SME thresholds for headcount, turnover and balance sheet assets were increased, meaning more companies were classified as SMEs and could claim under the SME route. Relief rates also shifted over this period as governments sought to keep the incentive attractive while managing cost and compliance.
2009-2015
2009
HMRC broadened the scope again by introducing the concept of Qualifying Indirect Activities (QIAs), reflecting that some supporting work can be directly required for R&D delivery, not just the hands-on technical experimentation.
2011
Corporation Tax reductions for non-SMEs continued through this period, reflecting a wider government aim to lower the headline rate.
2012
April 2012 brought further Corporation Tax reductions and changes to how Externally Provided Workers (EPWs) were defined for R&D purposes. This made it easier for some companies to claim where they relied on agency staff and specialist temporary labour.
2013
In April 2013, RDEC (Research and Development Expenditure Credit) was introduced, replacing the previous large-company scheme. RDEC was designed to be more visible in company accounts and more straightforward to access for large and loss-making companies.
2015
By 2015, Corporation Tax reached 20% for all companies at the time. The SME enhancement was increased and tighter rules were introduced around some cost categories, reflecting a continuing cycle of expansion and compliance tightening.
2016-2022
2016
After running alongside RDEC, the old large company super-deduction approach was fully phased out, leaving RDEC as the primary route for large companies.
2019
2019 marked a turning point in compliance. Government and HMRC attention increasingly focused on improving claim quality and reducing abuse. Digital submission processes and changes to reporting expectations built the foundations for the stricter validity checks that arrived later.
2020
In 2020, the RDEC rate increased from 12% to 13%, applying from 1 April 2020.
2021-2022
The government continued its review of the reliefs, aiming to modernise the scheme, protect taxpayer value, and reflect how R&D is actually delivered in modern businesses. This period laid the groundwork for the major changes that followed from 2023 onwards.
2023-2026: major changes to R&D tax relief
By 2023, reform moved from consultation into concrete rule changes.
April 2023: modernisation and rate changes
From 1 April 2023, the RDEC rate increased from 13% to 20% and the scope of qualifying expenditure expanded to better reflect modern R&D delivery, including data and cloud computing. Guidance also clarified that pure mathematics can qualify where it meets the definition of R&D for tax.
From April 2023, the overseas restrictions also came in for subcontractors and EPWs, requiring qualifying expenditure to be UK-based unless narrow qualifying overseas conditions apply.
August 2023: new “validity” requirements
From 8 August 2023, new legislation introduced additional requirements affecting claim validity, including claim notification in certain circumstances and the requirement to provide additional information alongside a claim.
HMRC also published practical guidance on submitting the Additional Information Form (AIF) as part of making a valid claim.
April 2024: the merged R&D scheme begins
For accounting periods beginning on or after 1 April 2024, the UK moved to a merged scheme, replacing the old SME and RDEC routes for most companies. ERIS sits alongside it for certain loss-making, R&D-intensive SMEs.
The merged scheme provides a taxable expenditure credit, keeping the “above-the-line” style credit structure familiar to many larger businesses while simplifying the overall landscape for most claimants.
2025–2026: a more evidence-led regime
By 2026, the pattern is well established. The relief remains valuable, but the regime now places more weight on clear project narratives, credible cost attribution, and contemporaneous evidence. For genuine innovators, this can be a positive shift, because well-evidenced claims claims are easier to support and defend.
How the R&D tax relief schemes have evolved
For many years, R&D tax relief operated through two main routes. This split affected not just the headline rates, but also how claims were calculated, how benefits showed up in the accounts, and how subcontracting and grants could impact eligibility.
They included:
- SME R&D relief for companies within the SME definition
- Research and Development Enhanced Credit (RDEC) for large companies (and SMEs in certain situations)
From 1 April 2024, most businesses now claim under the merged R&D expenditure credit scheme, which brings the system closer to the RDEC-style “above-the-line” credit approach and aims to simplify the landscape.
A separate route, ERIS, remains available for some loss-making SMEs that are genuinely R&D-intensive, giving additional support where R&D spend makes up a significant proportion of total expenditure. In practice, this means the starting point for most companies in 2026 is no longer “are we SME or large?”, but “which scheme applies to this accounting period, and do we meet the conditions for ERIS?”.
What are the benefits of R&D tax credits?
The business benefits remain consistent, even as the rules evolve:
- A rebate on your Corporation Tax
- A payable tax credit or cash
- An enhanced deduction for loss-making, R&D intensive SMEs
- Improved cash flow
- Extension of funding
- A stronger innovation story for investors and stakeholders
What counts as R&D?
R&D for tax purposes is defined as projects seeking an advance in science or technology through resolving scientific or technological uncertainty. It can apply in any sector, and projects do not need to succeed to qualify.
This can include the development of a new:
- Product
- Process
- Service
- Device
- Knowledge
It also includes the improvement of any of the above.

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