As a merchant, the ability to accept credit cards for payments is important to the overall success of your business. Millions of people pay for their transactions with the use of “plastic”. If you are unable to accept credit cards, you run the risk of losing out on thousands of dollars in profit.
However, as a merchant, accepting credit card payments also means having to pay processing fees for each purchase. One way that merchants can help their bottom line is to set a minimum purchase amount for credit card transactions. 
The Dodd-Frank Wall Street Reform and Consumer Protection Act gives merchants the power to impose minimum credit card purchase amounts. The act went into effect in 2010 and with it came the right for you to set a minimum purchase amount of no more than $10. The act also allows for this $10 minimum to be raised in the future, if the Federal Reserve Board decides it should be raised.
You may be wondering what this means for you, as a merchant. It means that you can help offset processing fees. For example, if the processing fees for a credit card transaction cost you $5 per transaction, small transactions are, essentially, costing you money. If a customer uses their credit card for a $3 transaction, you lose $2. The minimum purchase amount ensures that you do not have to lose money on small transactions.
On the other hand, you could also lose customers if you impose a minimum purchase amount. Customers enjoy the convenience of paying with a credit card and may not want to worry about whether they are buying enough to use their plastic. Some customers may even take their business elsewhere if they feel imposed upon by minimum purchase amounts.
It is up to you to decide if you want to use a minimum purchase – weigh your options carefully and make the choice that is best for your business.