Estimate UK R&D tax credit benefit under the SME scheme, merged RDEC scheme or pre-April-2023 SME rules.
Pick the scheme
Choose merged RDEC (most periods from 1 April 2024), SME (pre-April-2024 periods or qualifying transitional claims), or ERIS R&D-intensive (loss-making SMEs with ≥30% R&D spend).
Enter qualifying R&D expenditure
Include staff costs, 65% of subcontractor/EPW costs (UK-territorial from April 2024), consumables, software, cloud and data costs. Exclude routine work without scientific or technological uncertainty.
Choose profit or loss position
For loss-making SMEs, you can surrender losses for a payable cash credit at 10% (or 14.5% if R&D-intensive). Profit-making SMEs get the saving as a reduction in their corporation tax bill.
Set the Corporation Tax rate
For 2025/26, profits above £250,000 use 25%, below £50,000 use 19%, and marginal relief applies in between. The merged scheme credit is taxable so the net benefit varies with CT rate.
File the claim
Submit a CT600 with L supplementary pages and the mandatory Additional Information Form (AIF) since August 2023. First-time claimants must also pre-notify HMRC within 6 months of the period end.
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Disclaimer: All results are estimates for guidance only and do not constitute financial, tax or legal advice. Always consult a qualified professional.