Section 73(1) and 73(2) assessments: Evasion
You should consider the possibility of evasion in cases where an under-declaration of tax is involved.
Although you need to be mindful of the assessment time limits, and especially the one year ‘evidence of facts’ Rule, see VAEC1300, you should not issue an assessment prematurely in cases where evasion is suspected.
Further guidance on this aspect is contained in the VAT Civil Evasion Penalty guidance.
In all cases where inaccuracies have been made by a trader you should consult Schedule 24 penalties guidance contained in CH80000.