Amazon Music has taken a major leap forward, expanding its catalog from about 2 million to 100 million songs that will be made available ad-free to Prime members as part of their existing $139 annual membership fee. Starting this week, Prime members can “shuffle play any artist, album, or playlist, plus stream a selection of All-Access playlists on demand” as well as “access the largest catalog of ad-free top podcasts,” the online retail giant said. The move underscores a new battleground for membership-focused retailers, including Costco and Walmart, who see streaming as an opportunity to add value.

The Wall Street Journal writes that Amazon Music “essentially” offers Prime members “the full functionality of Spotify’s free tier but without ads,” allowing them to shuffle albums, playlists and artists’ catalogs, while stopping short of letting them select specific songs, a feature reserved for paid tiers.

WSJ says Amazon has the third-largest music service in the world, by subscriptions, right behind Apple Music and Spotify. It has “drawn a diverse and older listening base across the U.S. — many of them first-time streamers — in large part through its Prime subscription service and voice-activated Echo speakers,” WSJ writes.

Amazon’s Prime music has served as a feeder to Amazon Music Unlimited, the company’s on-demand subscription service, which costs $9.99 a month ($8.99 with Prime). As with the other big music services, Amazon also offers family and student plans, and also has a single-device plan for $4.99 a month that provides on-demand access to one Fire TV or Echo device.

By offering Prime members ad-free music, “Amazon will have to shoulder a potentially higher cost” of fees to record labels, “depending on how much more users stream,” WSJ says, calling Amazon Prime “one of the most successful subscription services, with more than 200 million members worldwide.”

Ad-free podcasts now available to Prime subscribers include lineups from CNN, NPR, ESPN and The New York Times, as well as the Wondery catalog and Amazon Exclusive show, the company said in an announcement.

WSJ writes that more entertainment companies are “bundling more offerings into their flagship apps,” mentioning The Walt Disney Company’s Disney+ selling merchandise, a move that may also expand to include promotional tie-ins with its theme parks. Google’s YouTube added a marketplace for streaming video services, while Walmart announced its Walmart+ subscribers now get free access to the basic tier of Paramount+.

“The biggest feedback we have gotten over the years is, ‘We love that this service comes with Prime, but we really want access to more music,’” Amazon Music VP Steve Boom says in an interview with The Verge’s Decoder that details the platform’s 10-year audio evolution, from selling MP3 downloads in 2012 to taking streaming “mainstream.”