Few letters cause more concern for a business owner than one from HMRC opening a compliance check or a full tax investigation.

However, an investigation is not automatically a sign that something has gone wrong and how a business responds in the early stages often has more bearing on the outcome than the original issue that triggered the enquiry.

Why HMRC investigations are on the rise

HMRC has significantly increased its use of data matching and automated risk profiling in recent years, cross referencing information from banks, online marketplaces, property records and other government departments to flag inconsistencies.

This means that investigations are increasingly triggered by data patterns rather than a specific tip off and can affect businesses that have made an honest error just as easily as those with more serious issues to answer for.

Common triggers include unexplained drops in turnover, expenses that appear high relative to industry norms, repeated late filing and inconsistencies between VAT returns and other submitted figures.

What to do the moment you receive a letter

The instinct for many business owners is to respond immediately and in detail, hoping to resolve the matter quickly. This is rarely the right approach.

Before replying to HMRC, gather the specific records requested and review them carefully with your accountant.

Agree exactly what will and will not be shared, since HMRC’s request will usually specify a scope and it is important not to volunteer information beyond that.

It is also worth confirming the deadline for response and requesting an extension early if more time is genuinely needed to gather accurate information, rather than submitting something rushed or incomplete.

Protecting your cash flow during an enquiry

Tax investigations can run for many months and in some cases considerably longer, particularly where the issues are complex or span several tax years.

During this period, it is sensible to set aside a contingency fund in case additional tax, interest, penalties or professional fees are ultimately due.

Businesses that have not planned for this can find themselves facing a significant and unexpected cash flow shock at the conclusion of an enquiry.

It is also worth reviewing whether tax investigation insurance is in place, which can cover the professional fees involved in managing a compliance check, allowing a business to engage proper representation without the cost becoming a further drain on resources.

Keeping day to day trading separate from the investigation, both financially and in terms of management attention, helps a business remain resilient and avoid the enquiry disrupting wider operations.

How we can help

Being investigated by HMRC can feel isolating, but you do not need to face it without support.

Our tax team has extensive experience managing enquiries and investigations on behalf of clients, from initial contact through to final resolution.

We can help you respond accurately and protect your position, while keeping the rest of your business running smoothly.

Get in touch as soon as you receive any correspondence from HMRC, so we can help you respond with confidence.