Amazon is trying to lure more subscribers to its $99 Prime loyalty program by pushing a day of discounts it calls "Prime Day."

The e-commerce retailer plans to offer thousands of deals on July 15 in the nine countries that have the Prime loyalty program, including the U.S., U.K., Spain, Japan, Italy, Germany, France, Canada and Austria.

The Seattle company says the promotion is pegged to its 20th anniversary, which is July 16. Amazon says there will be more deals on July 15 than on Black Friday, the busy shopping day after Thanksgiving, and Cyber Monday, the Monday after Thanksgiving when many people go online to shop for deals.

Amazon doesn't release the number of Prime members it has, but Michael Pachter, an analyst at Wedbush Securities, estimates there are 35 million to 40 million.

Amazon.com Inc. has been expanding its Prime program's offerings in an effort to add members, with additions such as grocery delivery, one-hour delivery in some cities, beefed up video streaming and the creation of a Bluetooth speaker called the Echo that syncs with Prime music.