Worldpay has teamed up with Amazon. Worldpay merchants that accept payments in the United States can now utilize Amazon Pay as an online checkout option. How it works: Through Worldpay’s API, online merchants can easily integrate and add Amazon Pay to their website. That means that buyers can choose to pay and checkout with Amazon Pay. “At Amazon, we are continuously looking for ways to invent and simplify on behalf of our customers,” said Patrick Gauthier, vice president at Amazon Pay. “Working with Worldpay will make it easier for merchants to grow their business by providing customers with a familiar and trusted experience throughout the shopping journey.” What's the deal: Worldpay is the first acquirer enabling Amazon Pay for its merchants. Amazon Pay hasn't achieved the same type of adoption that PayPal or Stripe has. According to Datanyze, Amazon Pay has 2.75 percent marketshare. An integration with Worldpay, which processes over 40 billion transactions yearly, can potentially put Amazon Pay in front of a lot more customers. This partnership is right off the heels of the news of the $43 billion merger of FIS and Worldpay, the payments industry's largest deal ever.