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HMRC internal manual

VAT Refunds

Unjust enrichment: Some items to consider: Can the recovery of input tax lead to unjust enrichment

The unjust enrichment defence may only be invoked against a claim made under section 80 of the VAT Act 1994 and, under that section, a trader can only make claims to recover amounts overdeclared as output tax - see the section on Section 80 claims for further information.

Late claims for input tax come under Section 25 of the VAT Act 1994 and Regulation 29 of the VAT Regulations 1995 which makes no provision for the refusal of a claim for unjust enrichment.

In other words, claims for output tax can be refused for unjust enrichment but claims for input tax cannot.