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HMRC internal manual

Guidance on the Audit of Customs Values

Other customs systems: handling operations in warehouse

When goods undergo any of the permitted forms of handling in warehouse, the declarant has the option of paying duty on the customs value applicable to the goods before the operation instead of paying duty on a customs value established when the goods are removed from the warehouse regime.

This option is likely to be appropriate only when a customs value is determined under Method 1, that is, the declarant has purchased the goods.

When the declarant is able to establish an acceptable value under Method 1 on the basis of a purchase price for the goods prior to their being subjected to an operation, that customs value is acceptable.