If HMRC opens an enquiry into your tax affairs, an accountant does four things for you: establishes exactly what is being checked and what HMRC is entitled to ask, gathers and reviews the relevant records before anything is handed over, manages every deadline in the process, and conducts the correspondence as your authorised representative. What no accountant can do is promise you a particular result. Anyone who does is telling you something about themselves, not about your case. The value lies in the process being handled correctly from the first letter onwards.
First: understanding what is actually being asked
HMRC calls these compliance checks, and GOV.UK explains the framework. Checks vary enormously in scope: a single question about one entry on one return is a different matter from a full review of a business’s records. The opening letter defines the scope, and reading it precisely is the first professional task.
This matters in both directions. Underreacting (a casual reply, a missed nuance) can extend a check that could have been closed quickly. Overreacting is just as costly: sending years of records nobody asked for widens the enquiry by invitation. An accountant identifies what is in scope, what HMRC is entitled to see, and what falls outside the check. Answering the question that was asked, fully and no wider, is the discipline that runs through the whole process.
Second: getting the records straight before anything is sent
Before responding, the accountant assembles the relevant records and reviews them the way HMRC will. That review establishes the position you are defending: whether the records fully support the return, and whether anything needs explaining.
If the records support the return, a clear response demonstrating that gives the check every reason to close quickly. If the review finds a genuine error, you need to know before HMRC points it out. Errors disclosed voluntarily and corrected are treated differently from errors uncovered, and your accountant will advise on the right way to put things right. What the process rewards is accuracy and candour, organised well; what it punishes is muddle. The habit of keeping records that can answer questions is covered in what information an accountant needs.
Third: running the timetable
Enquiry correspondence comes with response deadlines, and missing them has consequences: formal information notices, penalties, and the erosion of goodwill that makes everything slower. An accountant logs every deadline, requests more time where there is a genuine reason, and makes sure nothing goes out late or, just as damaging, goes out rushed.
The timetable also runs in the other direction. Checks can drift, and a taxpayer dealing with HMRC alone often lets them. An accountant chases progress, asks what remains outstanding and, where a check has run its course, presses for it to be concluded. There are formal routes for challenging both the conduct and the conclusions of a check, and part of representation is knowing when to use them.
Fourth: being your representative
Once authorised as your agent, your accountant corresponds with HMRC directly, attends any meetings with you or on your behalf, and frames responses accurately in a process where wording matters. Most people find dealing with HMRC stressful; an experienced representative has seen the process many times, knows what is routine and what is not, and can tell you honestly which is which. That steadiness, knowing your response is professionally handled and nothing is being missed, is a large part of what you are paying for.
Representation also protects you from unforced errors: the offhand comment that creates a new line of questioning, the volunteered document that widens scope, the defensive tone that hardens a routine check into a contested one.
What an accountant will not do
A reputable accountant will not promise the enquiry will be dropped, assure you that no tax will be due, or advise you to withhold something HMRC is entitled to see. Outcomes depend on the facts, and the facts are already what they are. What good representation ensures is that the facts are presented accurately and completely, your rights are exercised, and nothing avoidable makes the position worse. The line between robust defence of a filed position and the arrangements HMRC exists to challenge is discussed in tax planning and tax avoidance.
If you are weighing up professional support more generally, what an accountant does for a small business sets out the full role.
Frequently asked questions
I have received an enquiry letter. What should I do first?
Send it to an accountant before replying, including noting the response deadline. The opening response sets the tone for the whole check, and it is much easier to start well than to recover.
Does an enquiry mean HMRC thinks I have done something wrong?
Not necessarily. Checks are opened for a range of reasons, and some are simply routine. GOV.UK’s guidance on compliance checks describes the process. What the letter means in your case is one of the first things an accountant will assess.
Can my accountant handle everything so I never speak to HMRC?
Correspondence, yes: an authorised agent deals with HMRC directly, and most checks are resolved in writing. Some checks involve meetings or visits; your accountant prepares you for those and attends. The responsibility for your tax affairs remains yours throughout.
What if the enquiry finds a mistake in my return?
Mistakes are corrected and any tax adjusted; how that is treated depends on the nature of the error and how it comes to light. Your accountant’s review is designed to find any such issue first, because a position you disclose is better than one that is discovered.
How long do enquiries take?
Anywhere from one exchange of letters to many months, depending on scope and complexity. Prompt, complete, well-organised responses are the one factor within your control, and they shorten most checks.
How we can help
Our tax investigations support handles compliance checks from the first letter to conclusion: scope, records, deadlines and every exchange with HMRC. If a letter has arrived, request a quote and speak to us before you reply.