Some supermarkets soon will begin testing an electronic payment system that allows customers to use their MOST bank cards to pay for groceries.

Internet Inc. of Reston, owner and operator of the MOST banking system, said the new payment system should make grocery shopping easier and quicker.

The program will be tested in supermarkets in the mid-Atlantic region and South by Internet Inc., which operates the fourth-largest electronic banking system in the country, and Deluxe Data Systems Inc. of Milwaukee, the country's largest processor of third-party electronic funds transfers.

"MOST cards are already in the hands of 14 million customers of more than 425 financial institutions throughout the Mid-Atlantic and Mid-South region," said David O'Connor, president and chief executive of Internet. "Now ... we can offer the customers of participating financial institutions immediate access to this fully automated supermarket payment system with a card they are already comfortable using.

"This system offers these consumers added flexibility and convenience in deciding how they will purchase their groceries and promises to shorten the time they spend in the check-out lines," he said.

The new product, specifically designed for use in supermarkets, will allow a variety of payment options, including use of the MOST automated teller machine card to pay for purchases. Additional payment options include credit cards, merchant courtesy cards and electronic checks.

O'Connor said using the MOST card is more convenient than writing a check and offers more safety than carrying cash.

Supermarkets also will benefit, O'Connor said.

"Supermarkets can create a data base on both the demographics and actual purchase behavior of individual customers to analyze the impact of promotions and coupons upon consumer behavior and target consumer segments for increased purchase frequency," O'Connor said.

"Secondly, the store can reduce their check losses, labor costs and fees, while increasing customer loyalty and thus increase the supermarket's market share and average sale per customer," O'Connor said.

Internet and Deluxe Data are working with financial institutions to select supermarket chains for pilot projects.

When a customer is ready to pay, the MOST card would be run through a magnetic stripe reader. Then the customer would enter a personal identification number into the system and authorize the amount of the purchase.

Courtesy terminals also could be provided so customers could check their account balances or frequent shopper program specials before entering the check-out lane.

In addition to the purchase of groceries, the system could potentially support video rentals, private label credit and electronic benefits such as food stamps and in some locations, patrons will be able to get extra cash.