Customs Valuation Evidence: What HMRC Expects Importers to Hold

The obligation to hold customs valuation evidence is often treated as a filing formality attached to the import declaration. In practice it is a standing evidentiary commitment that extends for the full record-retention period applicable to the transaction, and the specific evidence required depends on which of the six WTO valuation methods was used to arrive at the declared value. A business that has documented its valuation methodology in general terms but has not mapped the evidence requirement method by method is likely to discover the gap only when HMRC asks.

The Legal Basis

The framework governing customs valuation derives from the WTO Agreement on the Implementation of Article VII of the General Agreement on Tariffs and Trade, which sets out a hierarchy of six valuation methods and is incorporated into UK law through the Customs (Import Duty) (EU Exit) Regulations 2018. Transaction value, the first and most commonly applied method, is the price actually paid or payable for the goods, adjusted for specified additions and exclusions. Where transaction value cannot be applied, because there is no sale or because the price is affected by conditions that cannot be quantified, importers must move sequentially through the remaining methods: identical goods, similar goods, deductive value, computed value, and a fallback method based on reasonable means.

Each method carries a distinct evidentiary standard, and the standard is set out in the 2018 Regulations rather than left to interpretation.

What Each Method Requires on File

For transaction value, HMRC expects the seller’s invoice or an equivalent document supporting the payment, together with evidence for any amount included, excluded, or adjusted under the additions and deductions provisions. Where the price is affected by contractual conditions, such as royalties, assists, or post-importation adjustments, the contract itself and the payment evidence must be capable of demonstrating how those elements were treated.

For the identical and similar goods methods, the business must be able to produce, or provide HMRC with the means to trace, a prior import entry for which a Method 1 transaction value was accepted, relating to goods that meet the specific comparability conditions set out in the Regulations. This evidence sits outside the transaction under review and requires the business to maintain a usable record of its own historical declarations, not only the transaction currently being examined.

The deductive value method requires a different evidentiary posture entirely. At the point of importation, a reasonable estimate of the eventual sales value must be supported by a pro forma invoice or an equivalent document. Once a sufficient volume of the goods has actually been sold, the business is required to submit the underlying sales invoices and the calculation of the unit price to HMRC’s National Import Duty Adjustment Centre, together with the detail of any deductions claimed. This is an evidentiary obligation that continues after the goods have cleared, not one that concludes at the border.

The computed value method requires evidence drawn from the producer’s own commercial accounts, prepared in accordance with generally accepted accounting principles in the country of production, covering both the cost or value of the materials and the producer’s profit and general expenses at a level consistent with other producers of the same class of goods for export to the UK. This is the most demanding evidentiary standard of the six, since it depends on financial records the importer may not directly control.

The fallback method, used only where none of the preceding five methods can be applied, still requires evidence. Where elements of the earlier methods are drawn upon in reaching a reasonable valuation, the evidentiary standard for those elements applies in the same way it would under the method from which they are taken.

Why the Gap Surfaces Too Late

The evidentiary burden under each method is precise, but it is rarely visible to the business until a valuation query is raised, because the goods clear and the transaction proceeds regardless of whether the underlying evidence has actually been retained in a usable form. A business applying transaction value correctly in the great majority of its declarations may hold none of the required evidence for the small proportion of transactions where a different method was needed, because those transactions were never flagged as requiring a different evidentiary standard at the point they occurred.

The practical response is not a general instruction to retain more documentation. It is a mapping exercise: identifying which valuation method applies to each category of transaction the business undertakes, and confirming that the specific evidence required under that method, as set out in the 2018 Regulations, is systematically captured rather than assumed to exist because a plausible-looking document is on file.

If you would like to check your current valuation evidence position against the method actually used for your transactions, feel free to reach out directly.