Pepsi teamed up with Waltham, Mass.-based SavingStar, a national paperless grocery savings service, to offer shoppers savings on Diet Pepsi and Pepsi Max. The savings is activated through the brands’ respective Facebook pages. During November, when shoppers spend $15 in total on any Diet Pepsi or Pepsi Max product at participating retailers over the course of any number of shopping trips, they will receive $5 back.

The promotion marks the first time a brand has offered fully digital savings to shoppers who purchase products and reach a threshold over multiple shopping trips and at multiple retailers, the company says.

“Pepsi strives to deliver value to our fans through innovative digital media,” said Shiv Singh, global head of digital for PepsiCo Beverages, in a statement. “This promotion allows us to reward our fans for their loyalty to our brands over multiple purchases in stores they love to shop. We’re excited to partner with SavingStar on this unique social promotion.”

In order to receive the discount, shoppers must activate the offer on Facebook, then register grocery and drug store loyalty cards from SavingStar’s digital network of more than 100 nationwide retailers, including Albertsons, CVS and Kroger. At the store, shoppers use their loyalty cards when they purchase any Diet Pepsi or Pepsi Max products.

Consumers can then track their progress toward the $15 spend requirement on the same Facebook tab where they activated the offer. When the goal is reached, SavingStar enables shoppers to cash out their $5 savings with direct deposit to any bank or PayPal account, an Amazon gift card or a donation to American Forests, a nonprofit conservation organization that will use funds to help plant trees.