Changes to HMRC's published details of deliberate defaulters: what could this mean for R&D tax claimants?

HMRC is seeking to change the rules on what it publishes about deliberate tax defaulters.

For R&D tax relief, one of the most significant changes is that HMRC may, for the first time, be able to publish enough information for readers to see that a deliberate default concerned an R&D claim.

At present, HMRC publishes the names of individuals and companies that have incurred penalties for deliberate non-compliance, but the published information does not make clear what the underlying issue was.

The draft legislation published on 13 July 2026, open for consultation responses until 7 September 2026, would let HMRC make the reasons a person or company appears on that list much clearer. It could, for example, show whether the issue involved a research and development (R&D) tax relief claim.

Adviser Radar responded to HMRC's consultation on 7 September 2026. We broadly supported greater transparency, and suggested some practical changes which we think would make the information more useful and reduce the risk of unrelated businesses being confused with a defaulting taxpayer.

What is changing?

HMRC already publishes details of some individuals and businesses who have received penalties for deliberate tax non-compliance. The power to do so is section 94 of Finance Act 2009, and HMRC's approach is set out in its Compliance Handbook at CH190100, Publishing details of deliberate tax defaulters, and the pages that follow it.

There are two separate strands to the changes.

First, the main publication threshold is being increased from £25,000 to £50,000 of potential lost revenue. The statutory instrument making that change was made on 9 September 2026 and comes into force on 2 October 2026. HMRC has said the higher threshold will apply from its November 2026 deliberate defaulters publication.

Second, the draft Finance Bill 2026-27 legislation would allow HMRC to publish more information about the underlying default, including details of the inaccuracy, failure or action which gave rise to the penalty, together with details of the penalty itself.

The draft legislation would also allow HMRC, in certain circumstances, to publish information about company officers where part of a relevant deliberate penalty has been transferred to them.

For most people using the list, the biggest practical change is likely to be the additional explanation of what actually happened.

Where do the different changes stand?

Measure	Current position
Main publication threshold raised from £25,000 to £50,000	Statutory instrument made. Comes into force on 2 October 2026
More detail about the underlying default	Draft Finance Bill 2026-27 measure
Publication of company officer information	Draft Finance Bill 2026-27 measure
Specific identification of R&D claims	Not expressly required. It may become possible if HMRC's descriptions are sufficiently detailed
Companies House registration numbers	Adviser Radar recommendation
Easier access for professional bodies and other users of the list	Adviser Radar recommendation

Could HMRC identify an R&D tax relief claim specifically?

Under the current regime, HMRC can publish identifying information, the penalties imposed and the potential lost revenue on which those penalties are based. What the list generally does not do is explain the nature of the default in enough detail to show whether an R&D tax relief claim, or any other specific issue, was involved.

The draft legislation would add a power to publish "details of the inaccuracy, failure or action giving rise to the penalty". That could allow an entry to make clear that the deliberate inaccuracy concerned an R&D tax relief claim.

The legislation does not require HMRC to identify an R&D claim. Whether it does so will depend on how HMRC uses the new power and how detailed its published descriptions are.

In our consultation response, Adviser Radar suggested that where an R&D claim was genuinely the subject of the deliberate penalty, HMRC should say so expressly. Identifying the tax only as Corporation Tax would still leave an important gap.

The change would not add detail to entries already published.

Does a published R&D claimant mean its R&D adviser acted dishonestly?

No.

The deliberate defaulters regime concerns the taxpayer which incurred the penalty.

If a company appears on the deliberate defaulters list because of an R&D claim, that does not by itself establish that the R&D adviser which prepared or supported the claim acted dishonestly. Tax advisers are covered by a separate statutory regime dealing with dishonest conduct by tax agents, in Schedule 38 to Finance Act 2012.

An R&D tax adviser could, however, appear on the list because of a deliberate penalty for non-compliance in its own tax affairs.

In our consultation response, we suggested that HMRC should identify an R&D tax relief claim where that is genuinely what the default concerned, but should avoid identifying or implying wrongdoing by an adviser unless there is a separate legal and evidential basis for doing so.

Why identifying the correct company matters

Better identification is not only about finding the defaulter. It is also about making sure an unrelated business is not mistaken for one.

HMRC generally identifies companies only by name and address. That can create problems. Company names change. Businesses move. Different companies can have very similar names. A company may also take over premises previously occupied by a completely unrelated business.

This is why Adviser Radar suggested that HMRC should routinely publish the Companies House company registration number (CRN) where the taxpayer is a registered company.

A company registration number identifies the legal entity itself. Names, addresses and trading styles can change. The company number does not. Including it would make it easier to identify the correct defaulter and reduce the risk of an innocent business being associated with somebody else's tax history.

The draft legislation does not require HMRC to publish company registration numbers. We pointed out that section 94(4)(f) already permits HMRC to publish "any such other information as the Commissioners consider it appropriate to publish in order to make clear the person's identity". We suggested HMRC consider whether publishing a CRN could therefore be adopted now, as a matter of publication policy, without further primary legislation.

Could HMRC's deliberate defaulters list become easier to search?

We believe it could.

HMRC says that, from June 2026, the deliberate defaulters list is published as an ODS spreadsheet.

Adviser Radar suggested going further. We suggested HMRC consider:

• publishing a CSV version with consistent field names
• including company registration numbers
• using reasonably consistent descriptions of the underlying default
• clearly identifying tax and penalty types
• including the date an entry was first published
• including the date HMRC's authority to continue publishing it expires
• an API for legitimate due diligence purposes.

Adviser Radar already checks HMRC's deliberate defaulters list as part of its wider media and public records checks on R&D advisers. This check is triggered only if an adviser firm itself is published as having received a deliberate tax penalty. The result feeds into the simple Red, Amber or Green indicator shown in that section of an adviser's profile.

What changes for company directors and officers?

Proposed new section 94A would allow HMRC, in certain circumstances, to publish information about a company officer where a qualifying notice has made that person liable to pay a portion of a company penalty for deliberate non-compliance.

The information which could be published includes the officer's name, address and position within the company, together with details of the relevant conduct, the penalties and the portion of the penalty for which the officer is liable.

There is a separate officer-specific threshold. The amount for which the officer is liable under the notice, or the aggregate amount where more than one penalty is covered, must exceed £25,000. That should not be confused with the main £50,000 potential lost revenue threshold for publishing the company or other taxpayer.

The officer must also be given a reasonable opportunity to make representations before publication, and both the penalty and the notice must have become final.

Adviser Radar supported the principle of publishing officers in appropriate cases, but questioned whether a private home address should ordinarily be published where a business, correspondence or service address would identify the individual adequately.

When will the wider changes take effect?

The richer descriptions and the company officer provisions are separate from the threshold change. They remain draft Finance Bill 2026-27 measures.

The draft legislation provides that the new publication powers would apply where the conduct or failure giving rise to the penalty occurred on or after the day on which the Act is passed. This remains subject to the Bill being enacted in that form.

If the provision is enacted as drafted, the richer descriptions will not be retrospective. Older R&D cases will not acquire more detailed descriptions simply because an enquiry concludes after the new rules begin.

There may therefore be a significant period before the practical effect of the reform becomes visible on HMRC's published list.

Why does this matter for R&D claimants?

For most compliant R&D claimants, the changes should have no direct effect.

These measures do not make a compliant claim, or a non-deliberate R&D error, publishable. However, where HMRC establishes deliberate non-compliance in connection with an R&D claim, and the statutory publication conditions are met, the claimant company's name, and potentially a director's name, could appear on HMRC's published list of deliberate defaulters.

This change is also being brought in at a time when HMRC is widening the range of conduct it can treat as serious non-compliance. The reckless untrue statements proposals would create a new criminal offence for statements made recklessly, and the proposed duty to correct errors in past returns could make failing to correct a known error a deliberate failure in its own right. Taken together, the three measures mean more R&D claimants could find themselves within reach of HMRC's most serious sanctions, including publication.

If HMRC uses the new powers to describe the underlying default clearly, it may become possible to distinguish between a company which has incurred a deliberate penalty relating to an R&D tax relief claim and one which appears on the list for an entirely unrelated tax issue.

These changes could also make HMRC's publication regime considerably more useful when carrying out checks on businesses.

At the same time, better identification is essential. Publication for serious tax non-compliance can affect reputation, commercial relationships and how third parties view a business. If HMRC publishes more information, users need to be able to tell what happened and who it actually relates to.

Adviser Radar's response

Adviser Radar submitted its response to HMRC on 7 September 2026. We broadly supported the direction of the proposals.

In particular, we suggested that HMRC should:

• make clear where the underlying deliberate inaccuracy concerned an R&D tax relief claim
• include Companies House registration numbers for companies
• make the published data easier to search and use
• use reasonably consistent descriptions of similar defaults
• maintain a clear distinction between the taxpayer and any tax adviser involved
• ensure that publication of company officer information is proportionate.

The aim is not simply to make deliberate non-compliance easier to identify. It is also to make the information more reliable, and to reduce the risk that an unrelated business or adviser is associated with conduct which was not theirs.

What happens next?

The £50,000 threshold change has been made by secondary legislation and comes into force on 2 October 2026.

The wider reforms, allowing HMRC to publish more information about the underlying default and about certain company officers, remain part of the draft Finance Bill 2026-27 legislation.