R&D Tax Credits for Construction Companies
Written and reviewed by the R&D Tax Accountants editorial team. Last reviewed 8 August 2026.
Construction is one of the largest under-claiming sectors for R&D relief. The work that qualifies is usually solved on site or in a design office under commercial pressure, recorded as a variation or a value engineering exercise, and never revisited.
The relief is about technological uncertainty, not about the size or difficulty of a project. A large complex building involves very little qualifying activity if every problem it presented had a known answer. A small scheme can involve a great deal if it did not.
What Counts as Construction R&D
The qualifying activity sits where a technical outcome was in doubt. Developing a structural solution for ground conditions that ruled out the standard approach, establishing whether a material could perform a function it was not designed for, achieving an acoustic or thermal performance that could not be reached with available systems, or devising a method of assembly where no proven sequence existed.
Work that does not qualify includes applying established construction methods to a new site, complying with building regulations, and the ordinary coordination of a complex programme. Regulatory compliance in particular is frequently mistaken for R&D because it is demanding and expensive, and demanding and expensive is not the test.
Prototyping and off-site trials of a proposed method are within scope where the outcome was uncertain. Capital expenditure, the cost of land, and rent, rates and leasing are excluded from the relief outright, as set out on the R&D tax credits guide.
Design Development Versus Buildability
The most common source of genuine qualifying activity in construction is the gap between a design that works on paper and a design that can actually be built. Resolving that gap is often where the real technological uncertainty was, and it is almost never recorded as research.
Where the contractor had to establish, without knowing whether it was possible, that a specified performance could be achieved with buildable details and available materials, that is a claim. Where the contractor selected a proven detail from a range of proven details, it is not. The distinction usually lives in RFIs, temporary works designs, mock-ups and failed trials, which is where the evidence for the claim comes from.
Who Claims on a Contracted Project
This is the question that decides most construction claims for periods beginning on or after 1 April 2024, and construction is the sector it affects most because almost everything is contracted. The right to claim contracted-out R&D sits with the company that decided on the R&D and planned it.
Where a client or lead designer specified an outcome and contemplated that development work would be needed, the claim may be theirs. Where a contractor or specialist subcontractor identified the problem and solved it on its own initiative, it may be the contractor's. Standard forms of contract were not written with this rule in mind, so the answer generally comes from project records rather than from the contract. The rule itself is on the merged R&D scheme page.
HMRC's definition of qualifying activity is in its guidance on claiming R&D tax relief, and companies looking at funded innovation projects alongside a claim should look at Innovate UK.