When one has a credit card and makes a purchase with the credit card, there is a balance. If the spending on this card is more than the predetermined balance, this is said to be an over-limit. Some credit card companies set the amount a card can be over-charged at a certain amount whereas others do not have such a cap. Once a card is over-limit, one may then be charged a fee for each transaction. The amount of this fee changes according to the company.
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