The Stop & Shop Supermarket Co. has become the latest grocer to introduce a seasonal program enabling shoppers to save on gas when they purchase groceries at participating stores. The per-gallon rewards thus earned will be automatically tracked and applied at the pump through customers' Stop & Shop cards.

"In this economy, every little bit of savings can add up and help families," said Stop & Shop's consumer advisor Andrea Astrachan. "Our new gas savings program makes it easy for consumers to save by doing something they already do -- their weekly grocery shopping."

Most New England Stop & Shop stores are offering the rewards. For every dollar spent on groceries, customers will earn one point, and for every 50 points they'll get 10 cents off per gallon on their next gas purchase at Stop & Shop.

Additionally, through a partnership with Christy's stores on Cape Cod in Massachusetts, Stop & Shop grocery customers at participating stores who buy $50 or more of groceries in a single transaction will earn a 20-cent-per-gallon reward that can be used at Christy's stores offering gasoline for purchase.

The new gas program provides savings on top of the five-cent-per-gallon discount already received by Stop & Shop cardholders.

The net grocery purchase excludes such items as alcoholic beverages, tobacco products, pharmacy items, gift cards, milk (Massachusetts only), lottery tickets, postage stamps, prepaid telephone calling cards, Western Union, money orders, and Metro passes. The limit is a one-vehicle fill-up, with a 20-gallon maximum, and the total discount can't exceed the price per gallon. Gas Rewards will expire 60 days from the date of issuance.

The promotion runs through Sept. 4.

Quincy, Mass.-based Stop & Shop, an Ahold USA banner, employs over 59,000 associates and operates 378 stores in Massachusetts, Connecticut, Rhode Island, Maine, New Hampshire, New York, and New Jersey.