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HMRC internal manual

VAT Assessments and Error Correction

How to assess and correct: Error correction procedures: VAT657 accompanying documents

The form VAT657 will always be accompanied by a form VAT667, Statement of Account.

Depending upon the circumstances it may also be accompanied by a VAT665, Notice of Amendment of Surcharge.

For periods prior to 1 December 1993 there may also be a VAT666, Notice of Amendment of Misdeclaration Penalty (MP).