Giant Food's credit-card rebate program, which has racked up millions of dollars in losses for three different banking partners since its launch in 1996, will be shut down Sept. 30.

First USA Bank N.A., now the issuer of the Giant Food Visa card, has begun informing customers that their cards will soon be replaced with First USA cards that will carry no annual fee but will earn no rebates and will not carry the Giant name. Customers will earn rebates through the end of next month. A spokesman said they will be mailed rebate certificates in October or November.

A spokesman for Giant Food Inc. said the decision to end the program was the bank's, but he promised that "we will be developing other merchandising and frequent-shopper programs in the future."

A First USA spokesman called it "a business decision."

Industry sources said First USA was suffering heavy losses on the program, even though the maximum rebate had been reduced to 1 percent late last year.

The program, which originally offered rebates of up to 3 percent on groceries bought at Giant and 1 percent on other purchases, is the latest victim of cutbacks across the industry as card issuers have found rebate programs far less profitable than they anticipated.

Far from attracting lucrative customers who carry large balances on their cards and pay handsome interest charges, as banks expected, rebate programs turned out to appeal instead to cost-conscious bargain hunters who make the most of the rebate and pay off their balances each month.

In many cases, the stores involved in rebate programs paid little or nothing, with the banks picking up most of the costs in hopes of building their credit-card portfolios. That strategy seemed appealing in the late 1980s and early '90s, when credit-card companies were generating large profits from consumers apparently unconcerned about interest charges, but it has not worked in recent years.

Giant's originally very generous program, which it began in partnership with M&T Bank N.A. of Buffalo, attracted a swarm of customers who charged far more than M&T anticipated and paid off their monthly balances in much greater numbers. The bank said it quickly accumulated 65,000 Giant Visa accounts when it had expected no more than 50,000.

Within a year M&T sought to pull out of the program; Giant filed suit to force it to continue. That suit was eventually settled, and the program was transferred to Chevy Chase Bank. Last year Chevy Chase sold its credit-card portfolio to First USA.

When it filed suit, Giant apparently felt its image would suffer if the program ended, but today it seems much less concerned. Indeed, some customers seemed unaware of the program or unconcerned about it.

Among daytime Giant shoppers interviewed at stores in Upper Marlboro and Loudoun County, none was aware of the card rebate, and none said they used the card.

"I'm unfamiliar with it, nor do I use it," said John Rey, who lives north of Baltimore.

Dunkirk resident Jessica Frost shops at Safeway and Giant with her two young children in tow, but she said that she's never had a Giant credit card and that the disappearance of the cash-back benefits will not affect her. But several callers to The Washington Post said they were unhappy to lose the rebates. Some said they shopped at Giant specifically for them.

"Many of these rewards programs have not worked very well" for the banks, said Robert B. McKinley, chief executive of CardWeb.com Inc., a Frederick firm that tracks the credit-card industry. But, he said, "they have worked very, very well for consumers--in fact, too well."

The problems of overly generous rebate programs have been compounded by changes in the credit-card market. "Convenience" use--by consumers who pay off their accounts each month--has risen from 29 percent of the market eight years ago to 42 percent now, "and it's rising each day," McKinley said.

Staff writers Yuki Noguchi and Sarah Schafer contributed to this report.