How to Run a Customs Compliance Health Check In-House

A customs compliance health check reviews your import declarations across five areas: classification, valuation, origin and preference, customs procedures, and documentation. To run one in-house you need your declaration data from HMRC, a structured set of checks for each area, and a process for turning findings into corrections and reclaims. This guide covers all three.

The case for doing it is straightforward. Benchmarks from over 190 UK organisations show that 17% of import declarations contain errors, and 14% of duty value is often overpaid. HMRC can assess underpayments for three years after clearance, and the same three-year window applies to reclaiming overpaid duty. Errors you find become recoveries; errors HMRC finds become demands.

What does a customs compliance health check cover?

A health check is a systematic review of your import declarations. It is not a full rehearsal of an HMRC post-clearance audit: the aim is to concentrate on the areas where errors are most common and where the financial exposure is greatest. Five areas do most of the work:

• Classification: commodity code accuracy and consistency.
• Valuation: the declared customs value, plus additions and deductions.
• Origin and preference: preferential claims and the evidence behind them.
• Procedures and reliefs: customs procedure codes and any reliefs you use or miss.
• Documentation: the audit trail supporting every declaration.

If you want a line-by-line worksheet to run alongside this guide, our customs audit checklist breaks the same ground into 15 specific checks. And if your question is how to score and prioritise whatever you find, see our companion piece on assessing your import risk, which covers risk scoring rather than execution.

What data do you need before you start?

Start with your declaration history. The Trader Records Extract (TRE) from HMRC gives you line-level detail for every declaration submitted through the Customs Declaration Service (CDS): commodity codes, customs values, duty and VAT amounts, preference codes, procedure codes and countries of origin. Request it through Government Gateway before you begin, because every check below depends on it.

Alongside the TRE, gather:

• Commercial invoices and packing lists for a sample of entries.
• Contracts, purchase orders and Incoterms for your main suppliers.
• Origin evidence: EUR.1 certificates, statements on origin and supplier declarations.
• Any classification rulings, valuation workings and broker instructions.

Pull two to three years of history where you can. HMRC's assessment window runs three years back, so a shorter view understates both your risk and your reclaim opportunity.

The Five Areas to Review

Work through the areas in order. Classification errors feed into valuation and origin findings, so fixing the foundation first saves rework later.

Area 1: Classification Accuracy

Commodity classification is the foundation of customs compliance. Errors here drive incorrect duty rates, wrong origin treatment and distorted trade statistics.

Key checks:

• Verify your commodity codes against the UK Trade Tariff, including duty rate and any measures.
• Review your top 20 commodity codes by volume and value.
• Look for classification drift over time: the same product declared under different codes.
• Check for inconsistencies across sites, systems and brokers.

Warning signs include multiple codes used for the same product family, frequent manual overrides of system-assigned codes, and an absence of written classification decisions or binding rulings.

Area 2: Valuation Methodology

Customs value errors feed straight into the duty you pay. Many importers overpay or underpay because the valuation method is not applied correctly or consistently.

Key checks:

• Confirm the valuation method used (typically the transaction value of the goods).
• Test sample entries to confirm the customs value calculation is correct for the Incoterms and invoice terms used.
• Look for non-dutiable charges wrongly included, such as post-importation inland freight, certain buying commissions, and post-import installation or construction costs.
• Look for dutiable additions that may be missing, such as assists (tooling, design or materials supplied free or at reduced cost), royalties and licence fees related to the imported goods, and certain commissions and packing costs.

Risk indicators: the same Incoterms treated differently across entries, no documented valuation policy, and inconsistent treatment of freight, insurance and surcharges.

Area 3: Origin and Preference Utilisation

Preferential origin reduces your duty bill, but only if claims are made correctly and the evidence stands up. Benchmarks show the average UK textile importer has a 53% preference utilisation gap: more than half of eligible imports pay full duty when a preferential rate was available.

Key checks:

• Calculate your preference utilisation rate: eligible imports against preferences actually claimed.
• Verify EUR.1 certificates, statements on origin and supplier declarations are valid, complete and correctly referenced.
• Confirm origin evidence is retained and linked to the right consignments.
• Identify entries where preference was available but not claimed. These can usually be reclaimed within the three-year window.

Area 4: Procedures and Reliefs

Customs procedure codes tell HMRC which regime your goods entered under. Wrong codes and missed reliefs both cost money, and both are common on high-volume accounts where brokers apply defaults.

Key checks:

• Review the procedure codes on your main trade lanes and confirm they match commercial reality.
• Check whether returned goods qualify for Returned Goods Relief rather than paying full duty again.
• Consider inward and outward processing where goods are repaired or processed across borders.
• Reconcile import VAT: postponed VAT accounting entries against your VAT returns, and C79 certificates where PVA was not used.

Area 5: Documentation and Audit Trail

Every finding above needs evidence. HMRC expects you to produce the documents behind any declaration on request, and a duty reclaim submitted on form C285 stands or falls on its paperwork.

Key checks:

• Confirm retention: customs records must be kept and retrievable for the statutory period.
• Trace a sample of declarations end to end, from purchase order through to the declaration itself.
• Check evidence linkage: origin proofs, valuation workings and rulings referenced against the right entries.
• Record who owns classification and valuation decisions, and when each was last reviewed.

How often should you run a health check?

Annually as a minimum; quarterly if you import at volume or your supply chain changes often. A workable pattern is a light quarterly review of your highest-value codes and lanes, with a full five-area review once a year.

Run an extra review after anything that shifts your risk profile: a new broker, a new sourcing country, a change of Incoterms, or a jump in declaration volume. The three-year windows also argue for regularity. Every quarter that passes without review lets the oldest overpayments drop out of reclaim scope, while unreviewed errors keep compounding your exposure.

From Findings to Fixes

A health check only pays off if findings become actions. Sort what you find into three buckets:

1. Overpayments: prepare duty reclaims. Overpaid duty can be recovered for up to three years through the C285 process.
2. Underpayments: take advice and consider voluntary disclosure. Coming forward is treated more favourably than waiting for HMRC to find the error.
3. Process gaps: fix the root cause, whether that is a broker instruction, a missing classification database or an unowned valuation policy.

Running these checks by hand across thousands of declaration lines is the hard part, which is why BorderAudit automates them. The platform pulls your HMRC data, applies the same five-area review to every line, and flags errors, missed preferences and reclaim opportunities as they appear. To see what an automated customs compliance health check would find in your own import history, check your eligibility for a free audit.