WOONSOCKET, R.I. — CVS Caremark Corp. is rewarding loyalty card customers who use new environmentally friendly shopping bags instead of single-use plastic bags.

Under the new GreenBagTag initiative, the drug store chain this week began offering ExtraCare cardholders Extra Bucks for declining plastic bags when making a purchase.

The program works as follows: For 99 cents, customers can buy the recyclable GreenBagTag — made with renewable, corn-based material and 100% recycled silicone, and packaged in 100% recycled paper — to attach to a reusable shopping bag or to carry along with their ExtraCare card. At checkout, shoppers who choose not to take a plastic bag, whether they’re using a reusable bag or simply carrying out their items, scan their GreenBagTag and ExtraCare card at the register.

On every fourth scan, GreenBagTag cardholders receive a $1 Extra Buck on the bottom of their receipt. Extra Bucks can be used toward a purchase on nearly anything in the store.

About 100 billion plastic shopping bags are used in the United States each year, and only 1% to 3% of the bags are recycled, CVS reported, citing figures from The Wall Street Journal.

The retailer’s ExtraCare loyalty program currently has more than 62 million cardholders, the company said.

"CVS/pharmacy is committed to improving the lives of the people and communities we serve, and that includes helping all our customers adopt more eco-friendly practices," Bari Harlam, CVS/pharmacy vice president of marketing, said in a statement. "Our new GreenBagTag program provides an easy way for shoppers to take a small step in going green, while also receiving Extra Bucks as a thank you for joining us in making an impact in the fight to reduce waste from disposable plastic bags."