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HMRC internal manual

Holding and Movements Export Shops

General structure and nature of the Export Shops warehousing regime: How the duty is calculated

At the end of an accounting period the duty liability (actual sales to non-entitledpassengers) is established and the advance payment is deducted from this amount.

At the same time the next advance payment is due and this is taken into account whenestablishing the duty amount to be paid. The net effect will usually be that the actualduty liability for the accounting period is the amount to be paid. The formula is asfollows

Actual Duty Liability, less Advance Payment paid last month, plus Advance Payment due.

Whilst this has the result of the advance payment acting like a deposit it is not to betreated as one. The advance payment can be changed and this will affect the duty due inthe accounting period when the new advance payment amount is first paid. See HMEXSH7010 for examples.