Sch 10B para 11
(1) This paragraph applies where, as part of a composite transaction— (a) goods or services are supplied to a person, and (b) a voucher is issued or transferred to that person. (2) If the total consideration for the transaction is not different, or not significantly different, from what it would be if the voucher were not issued or transferred, the paragraph 3 supply is to be treated as being made for no consideration.