Traditionally, the most popular pricing structure for merchant accounts has been a tiered rate model Under the common three-tiered system, merchant accounts have a base rate (referred to as a "qualified rate") and two subsequent tiers that determine a surcharge that is added to the base rate

The Merchant's Standpoint: It's an all too common headache for customers: They attempt to pay for a small purchase with a credit card, only to be informed that cards are only accepted for amounts over a certain minimum Merchants who impose minimums aren't purposely causing customers headaches, however, and there's an understandable reason for these purchase restrictions: the merchant can actually lose money on smaller purchases when the processing fees are larger than their profit on the sale