PITTSBURGH -- With high gas prices receiving most of the attention on gas station signs these days, many customers are failing to notice how businesses charge them based on how they pay.

As a result, those who are using plastic could be paying more.

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“It's not good -- not good at all,” said Wilkinsburg resident Ali Curges. “I want to be able to use my card the way it is without being charged for it.”

An increasing number of stations in Southwestern Pennsylvania and across the country are charging an additional 8 to 10 cents more per gallon for customers paying by credit card.

Every time a customer uses a credit card, stations are required to pay about a 3.5 percent transaction fee to the card company.

With gas prices hovering above $4, that equals more than 10 cents per gallon.

“If they charge me for it, I go somewhere else,” Curges said.

Bill Murray, of Murray’s Service in Wilkinsburg, said it’s far from a ploy to increase profits.

“Even charging a fee -- about 90 percent of the time you lose [money] or break even,” said Murray.

The American Automobile Association (AAA) warns drivers to look more closely to notice additional fees.

“It’s important they post both prices so that the motorist can make an informed decision,” said AAA spokeswoman Bevi Powell.

According to state law, both prices must be clearly displayed somewhere.

Customers who find a station where both prices are not posted can report it to the state attorney general.