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HMRC internal manual

VAT Registration

Registration - general: issue of VAT 1 to traders

The following categories may be used to code requests for VAT 1 forms:

A when an enquiry is received from a trader (in person, in writing or by telephone)
B at the request of a professional adviser
C when you think that a trader is making taxable supplies, but you are not sure whether they are liable to be registered
D when there is positive evidence to show that a trader is making taxable supplies above the registration threshold and he has failed to notify (this proof could be in the form of invoices for amounts in excess of the limit, or information that the business has been taken over as a TOGC).

The recording of enquiries about registration, issue of VAT packs and subsequent follow up action are explained in VATREG05000. In general, only Category C and D requests are recorded.