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HMRC internal manual

Guidance on the Audit of Customs Values

Method 1 (transaction value): valuation treatment

Method 1 is based on the price actually paid or payable for the goods.

The price actually paid or payable is the total payment made or to be made by the buyer to the seller for the imported goods.

Thus, in the case of contracts containing a review clause or providing for a retrospective price adjustment, the transaction value of the imported goods must be based on the total final price payable in accordance with the contractual stipulations.