Enhanced R&D Intensive Support

Enhanced R&D Intensive Support, usually called ERIS, is a UK research tax-relief scheme for eligible loss-making small and medium-sized companies. It combines an additional deduction for qualifying research costs with a payable credit against surrenderable losses. It preserves a distinct route for research-intensive businesses within the wider Reform of company research relief. [HMRC scheme history](https://www.GOV.UK/government/statistics/corporate-tax-research-and-development-tax-credit/research-and-development-tax-credits-statistics-september-2026)

Eligibility depends on a company making a tax trading loss before the extra deduction and meeting the research-intensity condition. Connected-company expenditure enters that assessment. The scheme has the same qualifying-cost rules as merged RDEC but calculates relief differently. An eligible business can choose merged RDEC instead, without claiming both schemes on the same expenditure. [HMRC guidance](https://www.GOV.UK/guidance/research-and-development-rd-tax-relief-the-merged-scheme-and-enhanced-rd-intensive-support)