R&D Tax Relief Calculator
Calculate your company's R&D tax relief under the merged RDEC scheme (April 2024 onwards), legacy SME scheme, or ERIS for R&D-intensive loss-making companies. Enter your qualifying R&D expenditure to see your tax benefit.
Tax Relief
£15,000
Effective Rate
15.00%
R&D Intensity
20.00%
Scheme
Merged R&D Scheme (RDEC-based)
Staff costs, subcontractor costs, consumables, software, and cloud computing
Used to calculate R&D intensity for ERIS eligibility (30% threshold)
From April 2024, the SME and RDEC schemes merged into a single scheme at 20%. ERIS remains for R&D-intensive SMEs.
| Qualifying R&D Spend | £100,000 |
| R&D Intensity | 20.00% |
| Applicable Scheme | Merged Scheme (20% RDEC, net 15.0%) |
| RDEC Credit (20.00%) | £20,000 |
| Less: Corporation Tax on Credit | -£5,000 |
| Net Tax Relief | £15,000 |
| Effective Relief Rate | 15.00% |
| Corporation Tax Rate | 25.00% |
Qualifying costs
- Staff costs (salaries, NI, pension for R&D workers)
- Subcontractor costs (65% for connected, 100% for unconnected)
- Consumables and materials used in R&D
- Software licences used for R&D
- Cloud computing and data costs (from April 2023)
Non-qualifying costs
- Capital expenditure (use capital allowances)
- Patent and IP costs
- Land and rent
- Production and distribution
- Quality control and routine testing
How UK R&D Tax Relief Works
R&D tax relief lets UK companies reduce their Corporation Tax bill — or receive a cash credit — for money spent on qualifying research and development. The relief is designed to encourage innovation by making it cheaper for companies to invest in developing new products, processes, and services.
The Merged Scheme (April 2024 onwards)
From 1 April 2024, the separate SME and RDEC schemes were merged into a single scheme for all companies. The new scheme provides a 20% R&D Expenditure Credit (RDEC) on qualifying spend. Because the credit is taxable, profitable companies paying 25% Corporation Tax receive a net benefit of 15% (20% credit minus 25% tax on the credit). Loss-making companies receive the full 20% as a payable credit after offsetting other tax liabilities.
ERIS — Enhanced R&D Intensive Support
ERIS provides a more generous regime for loss-making SMEs that spend at least 30% of their total expenditure on R&D. Qualifying companies can claim the 186% enhanced deduction (same as the old SME scheme) and surrender the resulting loss for a payable credit at 27% — significantly higher than the standard 10% rate. This gives an effective cash benefit of approximately 50.2% of R&D expenditure, making it one of the most generous R&D incentives in the world.
Legacy SME Scheme (pre-April 2024)
For accounting periods starting before April 2024, SMEs (under 500 employees, turnover under €100m or balance sheet under €86m) could claim an enhanced deduction of 86% on qualifying R&D spend. This meant the total deduction was 186% of the expenditure. Profitable companies benefited from a tax saving of 21.5% on R&D spend (86% × 25%). Loss-making SMEs could surrender losses for a 10% payable credit.
RDEC for Large Companies (pre-April 2024)
Large companies used the RDEC scheme, receiving a 20% above-the-line credit. Because the credit itself is subject to Corporation Tax, the net benefit for a profitable company paying 25% tax was 15% of qualifying expenditure. Loss-making large companies could receive the credit as a cash payment.
Key Rules
Claim deadline: R&D tax relief claims must be made within 2 years of the end of the accounting period to which they relate. For a period ending 31 March 2025, the claim deadline is 31 March 2027.
Advance notification: From April 2023, companies making their first R&D claim (or that haven't claimed in the previous 3 years) must submit an advance notification to HMRC within 6 months of the end of the accounting period.
Additional Information Form: All R&D claims must include a completed Additional Information Form, submitted before or with the CT600. This requires a named senior officer, a description of R&D activities, and a breakdown of qualifying costs.
Definition of R&D: HMRC follows the DSIT (Department for Science, Innovation and Technology) guidelines. R&D must seek an advance in science or technology by resolving scientific or technological uncertainty. Routine development, aesthetic design, and social science research do not qualify.
Frequently asked questions
What is the R&D tax relief rate for 2024-25?
From April 2024, most companies claim under the merged R&D scheme at a 20% RDEC rate. For profitable companies paying 25% Corporation Tax, the net benefit is 15% of qualifying R&D expenditure. R&D-intensive loss-making SMEs can claim under ERIS at a 27% payable credit rate.
What is the merged R&D scheme?
From April 2024, the separate SME and RDEC schemes were merged into a single scheme based on the RDEC model. All companies now claim an above-the-line R&D Expenditure Credit at 20% of qualifying spend. The exception is ERIS for loss-making SMEs spending 30%+ on R&D.
What is ERIS and who qualifies?
ERIS (Enhanced R&D Intensive Support) is for loss-making SMEs that spend at least 30% of total expenditure on R&D. Qualifying companies can claim a 27% payable credit on their surrenderable loss (186% of qualifying spend), giving an effective rate of about 50.2%.
How does the SME scheme work (pre-April 2024)?
The legacy SME scheme gave an enhanced deduction of 86% on top of the normal 100% deduction (186% total). For profitable companies at 25% CT, this gave 21.5% effective relief. Loss-making SMEs could surrender losses for a 10% payable credit.
What costs qualify for R&D tax relief?
Qualifying costs include staff costs for R&D workers, subcontractor costs, consumables, software licences, and cloud computing costs (from April 2023). Capital expenditure, patent costs, land, and routine testing do not qualify.
How is R&D intensity calculated?
R&D intensity is qualifying R&D expenditure divided by total company expenditure. If 30% or more, a loss-making SME qualifies for ERIS. Total expenditure includes all operating costs but excludes Corporation Tax payments.