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HMRC internal manual

VAT Small and Medium Enterprises Assurance Manual

Post Audit Action: errors discovered in value of outputs or inputs on the VAT return

When the trader’s total annual turnover is £250,000 or more and there are errors to the relevant boxes of the VAT return, which are likely to affect the gross mark-up for periods examined by 10% or more, corrections should be notified on Form VAT 480. Similarly, errors to global declaration values are corrected on Form VAT 479. This is input direct via VALID. When actual values per period cannot be ascertained, apportionment should be made on the basis of best estimates.