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HMRC enquiry defence

HMRC has questions about an R&D claim. We deal with them.

Whether the claim is yours or was prepared by a previous adviser, we triage the letter the same working day, review the evidence and defend the claim from the first reply to closure. We reply the same working day.

What an enquiry is

HMRC checks more R&D claims than it used to.

An HMRC R&D enquiry, formally a compliance check, is HMRC examining whether the relief on a claim was correctly claimed. It usually starts with a letter asking about the projects, the costs and the evidence behind them.

HMRC's own figures for 2023-24 show how much attention these claims now get:

  • 9,700 compliance checks, up from 8,300 the year before.
  • 17% of claims checked, compared with 10% the year before.
  • 77% of checks led to an adjustment.
  • £441m identified as incorrectly claimed.
  • 246 days on average to complete a check.

Source: HMRC's approach to research and development tax reliefs 2023 to 2024 (opens in a new tab).

Sound familiar?

Four situations we deal with often.

A letter about a claim we made

HMRC has written about a claim prepared by us or by your own team. We review the claim, agree what to send and handle the reply.

A claim prepared by a previous adviser

The adviser who prepared the claim has gone quiet or stopped responding. We take over, rebuild the technical case and defend the claim as it stands.

A nudge or one-to-many letter

HMRC has sent a general letter suggesting a claim may contain an error. We review the claim against the points raised and advise on a reply.

HMRC wants to meet the engineers

HMRC has asked to speak to the people who did the work. We prepare your competent professionals and attend the meeting with you.

How we defend a claim

From the first letter to closure.

  1. Triage the same working day

    Send us the letter. We read it, note the reply date, and tell you what it means and what happens next. We reply the same working day.

  2. Authorisation

    You authorise us as your agent. Agents must be named on the claim notification and the additional information form, so we are open about who is acting.

  3. Review of the claim and the evidence

    We review the projects, the costs, the technical report and the records against the Government's guidelines and HMRC's published approach. You hear our honest view of how strong the claim is.

  4. The technical case and written responses

    We build the technical case, decide what to send and write the responses. Nothing goes to HMRC without your sign-off.

  5. Preparing your competent professionals

    The people who did the work are best placed to explain it. We brief them on likely questions and how to answer clearly and accurately.

  6. Meetings with HMRC

    If HMRC wants to meet, we attend with you, keep the discussion on the evidence and follow up in writing.

  7. Closure

    We work towards a closure notice that confirms the claim, check the working behind any HMRC proposal, and advise on whether to accept or challenge it.

  8. Correcting the claim, if needed

    If the review shows something was overstated, we tell you first and set out the options, including telling HMRC unprompted, which generally leads to lower penalties.

Our record

What we can say, and what we cannot.

  • 30+ R&D claims prepared each year.
  • No R&D claim we have prepared has been rejected or reduced after an HMRC enquiry.
  • Every claim reviewed and signed off by a Chartered Tax Adviser.
  • We also defend R&D enquiries on claims prepared by others.
  • We reply the same working day.

This is a record, not a promise. Every enquiry turns on its own facts, and we will always tell you plainly where your claim is strong and where it is not.

Zero Risk includes enquiry defence

Defence is built into our Zero Risk package.

If HMRC opens an enquiry into a Zero Risk claim, we defend it end to end, at no extra cost. For claims prepared by others, or enquiries already open, book a call and we will explain the options. See how our packages work.

Zero Risk claims come with a full fee refund if HMRC rejects the claim outright after an enquiry. Conditions apply.

What to do now

What to do, and what to avoid.

  • Do not ignore the letter. A missed reply date makes matters worse.
  • Note the reply date and tell us at once.
  • Send us the letter, and any earlier correspondence about the claim.
  • Do not send everything HMRC asks for blindly. The first reply sets the tone, and it is hard to take back.
  • Keep the records safe, including emails, timesheets and test notes.
  • Avoid trying to fix it yourself by contacting the previous adviser or HMRC before you have had advice.

FAQs

Frequently asked questions

What is an HMRC R&D compliance check?

It is HMRC examining an R&D claim to decide whether the relief was correctly claimed. HMRC writes to the company, or its agent, asking questions about the projects, the costs and the evidence behind them. Some checks end quickly with no change, some lead to an adjustment, and some are settled by agreement. A letter does not mean the claim is wrong, but it does need a considered reply.

How common are HMRC R&D checks?

HMRC's own figures for 2023-24 show 9,700 compliance checks, up from 8,300 in 2022-23, covering 17% of claims compared with 10% the year before. HMRC had more than 500 staff working on R&D compliance, against about 100 in 2020-21. So a check is no longer unusual, and being prepared for one is part of any sensible claim.

How long do HMRC R&D enquiries take?

HMRC reports that checks completed in 2023-24 took 246 days on average. Individual cases vary a great deal, depending on how complex the claim is, how quickly information is supplied and whether a meeting is needed. A clear, well-organised response at the start tends to shorten the process, which is why we triage every case the same working day.

What does HMRC usually ask for first in an R&D enquiry?

Typically a set of questions about the projects and the costs: what the technological uncertainty was, who the competent professionals were, how staff time was apportioned and how the figures were built. HMRC may also ask for the technical report and supporting records. We read the letter closely and decide with you what to send, rather than sending everything on request.

Should we reply to HMRC ourselves or hand it to you?

You can reply yourselves, but a first reply sets the tone for the whole enquiry and is hard to retract. We recommend letting us review the claim before anything is sent. Once you authorise us as your agent, we correspond with HMRC, you stay informed at each step, and you decide anything that needs a business decision.

Can you take over an enquiry that is already running?

Yes. If HMRC has already written, tell us the reply date and send us the letter. We triage the same working day, then review the claim, the correspondence so far and the evidence before we respond. Taking over mid-enquiry is common, particularly where a previous adviser has gone quiet or has stopped responding to HMRC.

Do you defend R&D claims that other firms prepared?

Yes. We also defend R&D enquiries on claims prepared by others. We start with an independent review of the projects, the costs and the records, then tell you plainly how strong the claim is. If something needs correcting, we explain the options before there is any contact with HMRC about it.

Will HMRC want to meet our engineers or developers?

Sometimes. HMRC may ask to speak to the people who did the work, because they are best placed to explain the uncertainty and how it was resolved. We prepare your competent professionals beforehand, explain what to expect, and attend the meeting with you so the technical story is told clearly and consistently with the written claim.

What is the R&D Anti-Abuse Unit?

It is the HMRC team that handles suspected abuse of R&D relief, at both customer and agent level. It works with the Advertising Standards Authority on false claims that a service is HMRC-approved. If your claim is with this unit, you should take advice before replying to anything. We can assess the position and explain what it means for you.

Can HMRC charge penalties after an R&D enquiry?

HMRC considers inaccuracy penalties where an error is careless or deliberate, and the level depends on behaviour. Penalties are lower where a company tells HMRC about the error unprompted. That is one reason we review a claim honestly at the start: if something needs correcting, how and when it is raised affects the outcome.

What if HMRC says our project is not R&D?

We test the project against the Government's guidelines on the meaning of R&D: whether there was an advance in science or technology, and whether a competent professional could readily have resolved the uncertainty. If the evidence supports the project, we set out the technical case in writing. If it does not, we tell you, and discuss what that means for the rest of the claim.

What is a closure notice?

A closure notice is how HMRC formally concludes an enquiry. It states HMRC's conclusion and any amendment to the return. If it confirms the claim as made, the enquiry is over. If it changes the claim, we explain the effect, check the working behind it and advise on whether to accept it or challenge it.

Does an enquiry delay our R&D payment?

It can. While HMRC is checking a claim, payment of the credit may be held back until the check is resolved, and the position depends on the facts of your case. We tell you what to expect for your claim at the triage stage so you can plan your cash flow accordingly.

What happens to our future claims after an enquiry?

An enquiry on one period does not stop you claiming in later ones, but HMRC will have seen how the company evidences its R&D. We use the enquiry to strengthen your records, so later claims rest on better evidence. Prior-year claims prepared the same way may be worth reviewing too.

What if the enquiry shows the claim needs correcting?

We tell you first, in confidence, and explain the options. If a claim has been overstated, the full overclaim must be repaid, even if an adviser took a fee from it. Telling HMRC unprompted generally leads to lower penalties, so we work out the correct figure and the best route for putting it right.

How do we authorise you to deal with HMRC?

You sign an authorisation so that we can act as your agent on the claim, and we then register with HMRC in the usual way. Agents have to be named on the claim notification and the additional information form, so we are open about who is acting. We guide you through the paperwork on the day we triage the case.

What is a nudge letter or one-to-many letter, and must we reply?

These are letters HMRC sends to many companies at once, suggesting a claim may contain an error and inviting the company to review it. They are not the same as an enquiry, but they should not be ignored. We review the claim against the points raised and help you decide whether a reply or a correction is needed.

Got a letter from HMRC about an R&D claim?

Tell us the reply date and we will triage it today. We reply the same working day.

Or write to taxadvisory@aswatax.co.uk

Last reviewed 11 October 2026
Chartered Tax Adviser
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