The time of supply is also known as the ‘tax point’ (TP).
Tax points are a vital part of the VAT system because:
(1)they determine the period for which the supplier must account for output tax and the date by which it must be accounted for to HMRC;
(2)they determine the period for which a VAT-registered customer may reclaim the input tax;
(3)they determine what bad debt refund may be claimed if the claimant made more than one supply to the same person and has not received full payment. Any part-payment is attributed to the supplies on the first-in first-out (‘FIFO’) basis, i.e. the earliest supply first, so the tax points must be considered;