Definition
Cosmetic uncertainty is an informal term used by HMRC officers and specialist advisers to describe apparent technical uncertainty that is not genuine scientific or technological uncertainty under the BIS Guidelines. It typically arises where a project is described using technical language but the underlying work is the routine application of established methods, documented best practice, or skilled adaptation of known techniques. Cosmetic uncertainty does not support a valid R&D tax relief claim.
How HMRC defines it
While the term does not appear in statute, HMRC's view of what is and is not genuine uncertainty is set out at CIRD81300 and in the BIS Guidelines at paragraphs 13 to 16. HMRC's R&D Compliance approach, published in 2023 in the Guidelines for Compliance GfC3, gives concrete examples of claims where apparent uncertainty was rejected as routine implementation.
Practical example
A web development agency claims R&D relief for building a bespoke e-commerce site using a mainstream framework. Although the project has commercial challenges, the technical steps follow standard documented patterns and there is no material uncertainty that a competent software engineer cannot readily resolve. HMRC characterises the claim as based on cosmetic rather than scientific or technological uncertainty and disallows it.