Who can apply for R&D advance assurance?

For full claim advance assurance: an SME making its first R&D claim, with turnover below £2 million and fewer than 50 employees, where no linked company in the group has claimed R&D relief before.

How many accounting periods does it cover?

Up to 3. If HMRC agrees advance assurance, it applies to the company's first three accounting periods.

Is there anything available if we are too large to qualify?

There is a separate targeted pilot that gives assurance on up to 2 specific complex or high-risk areas of a claim. It is narrower in scope than full assurance but is not limited to first-time claimants in the same way.

Does advance assurance guarantee the claim will be paid?

It gives HMRC agreement on the basis described in the application, and HMRC may contact the company after the first claim to check the claim matches it. A claim that departs from what was described is not covered by what was agreed.

R&D Advance Assurance Applications

Written and reviewed by the R&D Tax Accountants editorial team. Last reviewed 8 August 2026.

Advance assurance lets a company put its R&D work to HMRC before claiming, and get agreement that covers its first three accounting periods. It is voluntary, it is free, and it is only open to a narrow group.

Where a company qualifies, it removes most of the uncertainty from the early claims. Where it does not, the alternative is a well-evidenced first claim rather than a substitute application.

What Advance Assurance Gives You

Full claim advance assurance applies to the company's first three accounting periods. If HMRC agrees it, it sends a letter setting out the company's responsibilities, and it may follow up after the first claim to check the claim matches what the application described.

The value is not only the certainty. Preparing an application forces a company to articulate its uncertainty and its record-keeping at the start, which is exactly the discipline that makes the first three claims defensible whether or not assurance is granted.

There is also a separate targeted pilot covering up to two specific complex or high-risk areas of a claim, for companies that do not need or cannot get full assurance but want a position settled on a particular point.

Who Cannot Apply

The conditions on full claim advance assurance are narrow. The company has to be an SME, it has to be its first R&D claim, turnover has to be below £2 million and it has to have fewer than 50 employees. If it is part of a group, no linked company can have claimed R&D relief before.

Those thresholds exclude most companies that come looking for it, including plenty of genuine first-time claimants who are simply larger than £2 million. The honest answer in that case is that assurance is not available and the effort belongs in the first claim instead.

How the Application Runs

The company can apply itself or an agent can apply for it, online through the Government Gateway or on a downloadable form. HMRC then contacts the company by email to arrange a call to discuss the R&D activities in more detail, and sends a decision letter afterwards.

The call is the substance of it. What HMRC is testing is whether the person describing the work can characterise the uncertainty, which is the same question a compliance check asks later. We prepare for it the same way, and the technical lead needs to be on it rather than the finance team.

HMRC sets out the conditions and the process in its advance assurance guidance. Companies at this stage are often also applying for grant funding, which runs separately through Innovate UK.

Fees for an Advance Assurance Application

The application itself costs nothing to submit. Our fee is for preparing it and for the call, agreed in writing before we start.

We check eligibility first and free of charge, because the thresholds rule out most enquiries and there is no point charging to establish that. If the company does not qualify, we say so and the conversation moves to the first claim.