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HMRC internal manual

Excise Repayment of Overpaid Duty

Claims for excise duty where there has been an error by HMRC: what about unjust enrichment

We are not entitled to refuse repayment on the grounds of unjust enrichment for claims made under the provisions of Schedule 3 of the Finance Act 2001. This is because Schedule 3 does not include in its provisions the unjust enrichment defence. This exclusion is by virtue of CEMA Section 137A(6), see ERODG3200.