How to Respond to an HMRC Customs Enquiry: Step-by-Step

To respond to an HMRC customs enquiry: acknowledge the letter promptly, confirm what HMRC has asked for and by when, gather the declaration records in scope, review your own data for errors first, and reply factually in writing. How you handle the first 14 days often determines whether it escalates to a full audit.

The letter usually comes from one of HMRC’s customs compliance teams and sets a deadline, commonly 30 days. It is not an accusation. It is a request for evidence. This guide covers what the enquiry means, the seven steps to follow when you respond, and how to avoid the mistakes that turn routine HMRC compliance checks into something larger.

What Is an HMRC Customs Enquiry?

A customs enquiry is a written request from HMRC for information about specific declarations, trade lanes, or compliance processes. It typically precedes a post-clearance audit and focuses on:

• Classification: the commodity codes behind your declared duty rates.
• Valuation: the customs value declared, including additions such as freight, royalties and assists.
• Origin: preferential origin claims and the certificates or statements behind them.
• Procedures: the customs procedure codes and any reliefs you have used.

HMRC selects enquiries from the declaration data it already holds. Your Customs Declaration Service (CDS) records are analysed against risk profiles, so a letter usually means an analyst has seen a pattern worth questioning: inconsistent codes for similar products, customs values that look low against peers, or preference claims without an obvious documentary basis.

“Trade lanes” matters here. An enquiry about one supplier route is rarely about a single declaration. HMRC is testing whether the treatment you applied across that lane, sometimes hundreds of declaration lines, stands up.

How Is an Enquiry Different from a Full Audit?

An enquiry is narrower and earlier. HMRC is asking questions about a defined set of declarations rather than opening a formal review of your whole customs operation. A post-clearance audit, by contrast, can cover any declaration made in the last three years and may involve information notices, site visits, staff interviews and formal findings.

The distinction matters because the enquiry is your chance to resolve the issue while it is still small. Clear, complete answers backed by documents often close the matter at desk level. Vague or late responses do the opposite: they confirm the risk profile that triggered the letter and invite a wider review. HMRC’s own guidance on compliance checks makes clear that the quality of your cooperation influences how a check proceeds and how any penalties are calculated.

How to Respond to a Customs Enquiry: Seven Steps

Step 1: Read the Letter and Confirm the Scope

Identify exactly which declarations, periods and topics HMRC has named, and note the deadline and the officer’s contact details. Answer what is asked, fully, and no more. Volunteering information about areas the letter does not cover widens the enquiry for no benefit.

Step 2: Acknowledge Receipt and Manage the Deadline

Reply promptly to confirm you have received the letter and will respond by the date given. If the records will take longer to assemble, ask for an extension early and explain why. A realistic request made in week one reads very differently from silence that ends in a late reply. Missing the deadline without contact is the single easiest way to escalate an enquiry, because HMRC can then assess from the data it holds, without your side of the story.

Step 3: Assemble the Records HMRC Has Asked For

Typical requests include customs declarations, commercial invoices, packing lists, transport documents, origin certificates and valuation workings. Pull your own declaration history alongside them. The Trader Records Extract (TRE) gives you line-level CDS data for every import, and automated HMRC data retrieval means you can see exactly what HMRC sees before you answer.

Step 4: Review Your Own Data Before You Reply

This is the step most importers skip, and the one that matters most. Check the declarations in scope for classification, valuation and origin errors before HMRC does. If your records support the declarations, you can answer with confidence. If they reveal a problem, you want to be the one who found it, because the disclosure options below depend on who identifies the error first.

Step 5: Answer Factually, in Writing

Respond in writing, reference declarations by Movement Reference Number (MRN), and attach the evidence rather than summarising it. Keep the tone factual. Do not speculate about why an error might have happened, and do not commit to process changes you have not yet made. If a question is ambiguous, ask the officer to clarify rather than guessing at the intent.

Step 6: Disclose Any Errors You Find

If your review uncovers underpaid duty, disclosing it before HMRC identifies it usually reduces any penalty. If you find overpayments, the same three-year window lets you reclaim them. Both routes are covered in the next section.

Step 7: Keep a Complete Record of the Exchange

File every letter, email, call note and document you send, with dates. If the enquiry escalates, or if you later appeal an assessment, the record of what you provided and when becomes part of your defence.

Should You Make a Voluntary Disclosure?

Yes, if your own review confirms an underpayment. Disclosing an error before HMRC identifies it usually reduces any penalty, and in some cases removes it altogether. For import declaration errors, the correction is made through a C2001 voluntary clearance amendment, which amends the declaration and settles the additional duty and import VAT.

Overpayments run the other way. If the review shows you paid too much, perhaps a higher duty rate than the correct commodity code carries, or a trade preference you never claimed, you can submit a C285 reclaim for declarations up to three years old. An enquiry that prompts a proper review of your data quite often ends with duty coming back rather than going out.

What Happens After You Respond?

HMRC will normally do one of three things:

1. Close the enquiry, sometimes with a letter confirming no further action.
2. Ask follow-up questions or request further documents, which keeps the matter at enquiry level.
3. Escalate: open a post-clearance audit, or issue a C18 demand for underpaid duty with interest and possible penalties.

If HMRC issues an assessment you disagree with, you can request an internal review or appeal to the First-tier Tribunal within the time limits set out in the decision letter. A well-documented enquiry response strengthens both routes, because your evidence and your timeline are already on file.

How Do You Reduce the Risk of the Next Enquiry?

Enquiries follow data. The importers who rarely receive them are the ones whose declarations are consistent, whose preference claims are documented, and who check their own records before HMRC does. In practice that means:

• Review your declaration data on a regular cycle rather than waiting for a letter.
• Keep origin, valuation and classification evidence linked to the declarations it supports.
• Fix systemic errors at the source, in broker instructions and product master data, not declaration by declaration.

BorderAudit automates that discipline. The platform pulls your CDS declaration history, runs automated checks across classification, valuation, origin and preference, and flags issues while they are still yours to fix. If you want to know where you stand before HMRC asks, check your eligibility for a free audit and see your declaration data the way an HMRC analyst does.