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HMRC internal manual

VAT Assessments and Error Correction

Section 73(1) and 73(2) assessments: Definition of underpayment and overpayment

An underpayment means that the amount declared on a return or error correction notification, or an amount assessed has not been paid in full.

An overpayment means that the amount paid exceeds the amount declared or assessed.

Under and overpayments are not the same as under and over-declarations, see VAEC2930.