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HMRC internal manual

Holding and Movements - Duty Stamps

When a Stamp May Be Applied: Accompanied personal imports from outside the European Community

As detailed at HMDS2330, goods which are imported by private individuals for their personal consumption, and on which any UK duty which is due has been paid, are excluded from the requirement to bear a duty stamp. The offences of possessing, holding and transporting unstamped goods do not apply provided that the goods are not sold on.