Your R&D tax credit claim is submitted along with your corporation tax return (CT600). HMRC does not provide a specific template for the supporting information, but they do specify the type of details they require for an R&D tax credit claim. This includes a breakdown of the qualifying expenditure and a description of your R&D activities.
After determining the R&D tax credit benefit, you must enter this information in your company tax return (CT600). This includes the enhanced qualifying R&D expenditure and, if applicable, the payable tax credit amount. Learn more about required documents for submitting R&D claims.