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HMRC internal manual

ATA/CPD Carnets Manual

ATA carnet procedures: valuation

UK/EU issued carnets

It is the responsibility of the issuing authority to ensure that the valuation being applied to the temporarily exported goods is correct. It is not the responsibility of customs to check the valuation at export.

Third country carnets

When a third country carnet is presented in the UK, the valuation of the goods is based on the valuation rules applicable in the country of issue. However, if the goods are diverted to free circulation, normal customs valuation rules apply (Istanbul Convention Article 13 Commentary (3)).

Notice 252 Valuation of imported goods for customs purposes, VAT and trade statistics (HMRC web) 

(This content has been withheld because of exemptions in the Freedom of Information Act 2000)