HOUSTON -- Maybe it's happened to you. You're standing in line to buy a soft drink or some other small item when you realize you've got no cash. So, you whip out the plastic only to discover the store wants to charge you a fee for using your card for such a small purchase.

Some viewers asked KPRC Local 2 investigative reporter Amy Davis if these fees are legal.

Davis has an answer that could save you some change. She said that if a merchant tries to charge you a fee that's more than the price of the item you're purchasing, just say no.

According to state law, those fees are illegal.

Davis said it makes sense that retailers would try to recoup what it costs them to accept credit cards.

On average, a convenience store will pay the credit card company about 3 percent of whatever is charged in that store.

For a $3 purchase, that's about 9 cents. But the merchant cannot legally recover that cost from you by charging a fee for minimum purchases.

We found it spelled out in the Texas Finance Code.

It reads, "In a sale of goods or services, a seller may not impose a surcharge on a buyer who uses a credit card for an extension of credit instead of cash, a check, or a similar means of payment."

The Texas Attorney General's office also points out that businesses that set minimum purchase limits or charge you processing fees on credit cards are also breaking the rules in the contracts they've signed with MasterCard, Visa and sometimes American Express.

If you see it happening, you can file a complaint with the AG’s office, but they say if you don't like the charge, you really should consider taking your business somewhere else.

More Information:

File Complaint With Attorney General
Texas Finance Code