Some suppliers may require prepayments for their products and services. The decision to provide payment in advance of receiving the good or service resides with the budget owner. However, prepayments to suppliers should be avoided when possible as they come with a number of risks; for example, should any issues arise (quality of product/services, delivery delays etc.) they can be difficult to resolve if payment has already been issued.
For more information, see the Prepayments section of the Guide To Financial Management (GTFM).