Cash is king. It's also the preferred method of payment for a wide range of businesses that offer a discount to their customers who pay cash.

Discounts can range from just a few percentage points to nearly half off, depending on the merchant and product. Though most people don't always know they're available, sometimes all you need to do is ask for it.

Gas Stations

Only about 5 percent to 10 percent of the 115,000 independent gas stations nationwide offer cash discounts, says Jeff Lenard, spokesman for the Alexandria, Va.-based National Association of Convenience Stores, a trade group representing gas station and convenience store owners. But that doesn't mean savvy consumers shouldn't be on the lookout for cash deals at the pump, he says. A recent association study found that where one gas station offers cash discounts, others in the area will likely follow.

As for the savings, Lenard says that customers who pay cash can typically trim 2 percent -- the merchant's typical fee for using plastic -- off the total. Based on an average gasoline price nationally of $2.72 a gallon, (Desk: Please check this before publishing at http://www.fuelgaugereport.com/. Thanks, sp.), Lenard estimates that cash will save customers about 5 cents a gallon. But when gas prices rise, the savings also increase, he says. Just don't expect a cash deal on anything inside the store. Lenard says convenience store owners don't offer cash discounts on things like candy and soda.

Restaurants

When Todd Beauchamp, an associate television producer in Los Angeles, ordered takeout one night from his local Thai restaurant, he couldn't believe his ears. If he were to pay cash, he would save 10 percent off the bill, the restaurant's owner told him.

"It was a no-brainer," says Beauchamp, who now routinely asks for a cash discount. "I've been pleasantly surprised by the number of restaurants that offer cash discounts."

According to Beauchamp, by asking around and keeping cash on hand, he can shave a few dollars off of his weekly takeout bill. Saving as much as $3 a week adds up to $150 or more a year.

An informal survey of restaurants around the country found 10 percent is the norm for cash discounts, but a few eateries took as much as 15 percent off the bill. However, of the more than 20 upscale restaurants that participated in the survey, none said they were offering a cash discount. So, customers should look for discounts at restaurants that do a large takeout or delivery business.

Doctors

Cash discounts are probably the last thing most people consider when visiting the doctor, but those who ask can often trim their medical bills, according to Carrie McLean, a Sacramento, Calif.-based consumer specialist at eHealthInsurance.com, a Web site that advises consumers on medical costs and health insurance plans. CQ, the company is based in Mountain View but this source is located in Sacramento. In some cases, consumers can cut their bills in half.

"If you don't have insurance and you go to the hospital, it's important to know that you'll typically get a 20 percent discount," McLean explains. "But you can always ask about cash terms, too. A lot of hospitals will take another 20 percent off for customers who pay cash within 30 days and 10 percent off for those who pay cash within 60 days."

But those with insurance also should look for opportunities to pay cash, especially if they're planning to have a procedure that won't be covered, McLean says.

"The thing to do is talk to your doctor's office manager beforehand," she says. "Often, the first price reflects an agreement between the insurance company and the health care provider so it's not what your doctor actually gets. And that means there's a lot more room to negotiate than people think."

Computer Repairs

You have to ask, but some independent computer repair firms will happily knock 5 percent off your bill if you pay cash.

"There's a much lower risk of headaches with cash transactions," says Adam Jamal Craig, owner of HyperNerd Inc., a computer repair business in Burbank, Calif.

Craig says he only offers the discount on services, not on hardware or software sales because those items tend to give him less room to negotiate. But even 5 percent can add up on a service bill.

For instance, Craig says he typically charges $200 to recover lost data from a damaged hard drive. While the primary concern for his customers is getting their data back, Craig says a lot of them are happy to pay cash if it means they get $10 off.

Jewelry purchases

If you've got the money to spend on jewelry, a discount may not be foremost on your mind, but it should be, says Inga Vascenkova, a brand manager for ItsHot.com, an online jewelry retailer in New York.

Discounts vary, but Vascenkova says that some items may be discounted by as much as 20 percent if the customer is willing to pay cash. With jewelry prices ranging from several hundred dollars into the thousands, the savings can be substantial. However, if the item is mostly gold, the discount will likely be less -- 5 or 10 percent, she warns.

Either way, getting a cash discount comes down to two things. "Customers must be willing to pay cash, and they have to ask," Vascenkova says.

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