When Palmerin Perez goes shopping, she will not leave home without it but it is not the American Express card.

Perez takes her debit card to pay for everything she buys, including the sweater she bought Wednesday at Westfield MainPlace mall in Santa Ana, Calif., and cannot imagine paying any other way.

“It takes (the money) directly out of my checking account,” said Perez, 30, of Union City, N.J., who is visiting in Orange County, Calif. “I never have to worry about credit.”

Perez is one of millions of Americans, especially younger consumers, who increasingly favor debit cards over other forms of payment.

A recent Harris Poll conducted for Visa USA showed when it comes to buying an article of fall clothing, such as a sweater or jeans, nearly half of the 1,562 people surveyed said they were most likely to use a debit card. Among 18- to 34-year olds such as Perez, 54 percent said they would use debit cards.

“That’s what we’re seeing across the board,” said Seth Eisen, a Visa spokesman. “More and more people are using debit cards for purchases.”

Cash, checks losing

Debit cards, which electronically deduct money directly from a consumer’s checking account, are just one more example of how modern technology is changing the way people handle their money.

Because of their convenience and widespread acceptance by merchants, debit cards are rapidly becoming the new cash. In fact, for the first time last year, cash and checks accounted for less than half the payments – 47 percent – for in-store purchases, according to a study by the American Bankers Association and Boston-based Dove Consulting Group. Just five years ago, they made up 57 percent.

During the same period, the study said, debit-card transactions increased from 21 percent five years ago to 31 percent as of last year.

Gerri Detweiler, president of Ultimate Credit Solutions Inc. and author of “The Ultimate Credit Handbook,” said consumers also need to watch out for other pitfalls when using debit cards.

“The biggest thing is that if you’re a victim of fraud, how fast do I get my money back into my (banking) account?” said Detweiler, who worked on a debit-card project with Bank of America last year.

Monitor your account

Consumers should monitor their accounts closely for any unauthorized transactions, she said. If your card is lost or stolen, you may also be liable for the first $50 in losses. With the Visa check card, there is no liability.

Fees are also an issue. Some banks and retailers charge fees for some debit-card transactions, so make sure you know how much it is going to cost, Detweiler advised.

Unlike credit cards, some debit-card companies also do not provide consumer protection for disputed purchases. If you are dealing with a local merchant and want to return something, that may not be a big problem, said Detweiler, but if a purchase is out of town or online, you may want to think twice about a using a debit card.

The Visa survey, however, showed cash still is king when it comes to one thing – checkout lines.

Of those surveyed, half voted for cash as the fastest way to check out, while only 29 percent saw debit cards as the quickest way to get out the door.

“We can all appreciate that,” said a Visa spokeswoman. “There’s nothing more irritating than being behind someone in line who pulls out their checkbook.”