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HMRC internal manual

VAT Assessments and Error Correction

How to assess and correct: VAT Amendments: VAT656 accompanying document

The form VAT656 will always be accompanied by form VAT667, Statement of Account.

Depending upon the circumstances it may also be accompanied by forms VAT665, Notice of Amendment of Surcharge and VAT666, Notice of Amendment of Misdeclaration Penalty (MP).