Discount card

A discount card is a card or document, often a plastic credit card or paper card, that entitles the holder to discounts on the prices of some products or services. Cards may be issued as part of a loyalty program, offering discounts to existing customers to ensure their continuing custom; they may be offered free of charge, offering a modest discount with the intention of persuading purchasers to patronise participating shops; or they may be sold to members, offering larger discounts—for example, the tastecard offers 50% discounts at many restaurants—at a substantial annual cost. Cards may be offered by merchants or groups of merchants, by clubs or associations who negotiate on behalf of all members to obtain benefits, or by official organisations offering concessionary prices to qualifying groups, such as the disabled.

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Wikipedia