A volume discount is a change to the cost of a product based on the quantity of that product traded with your trading partner. Typically, volume discounts are paid retrospectively so sit under the wider banner of rebate, although sometimes these volume discounts can be up front.
This potential retrospectivity often depends on whether different discounts apply to incremental tiers of volumes traded with a specific trading partner throughout the course of the year, meaning that you are unsure of the value of the discount until the year end.
Volume discounts are often used by suppliers to incentivize greater purchase volumes and are available due to the advantages brought about by economies of scale. This has the side effect of increasing the suppliers market share and presence in the marketplace because increasing quantities of their products are being traded.
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