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HMRC internal manual

VAT Assessments and Error Correction

Power of assessment: Evidence of fact: What is evidence of fact

In order to make a four year assessment under Section 77(1) VATA94 or a twenty year assessment under Section 77(4) VATA94 an officer must make the assessment within one year of the evidence of facts.

This should be interpreted to be the date on which the last piece of relevant evidence was communicated to the Commissioners in order to justify the making of the assessment.