My favorite feature of these Audible trials is that once you get a book, it remains available permanently. If you don’t have Amazon Prime, you could start a 30-day free trial. This promotion appears to work even if you are a past Audible member (trial or otherwise), but not if you are an existing active member. And Amazon has been looking for more ways to include exclusive video content into Prime memberships benefits, so it makes sense that audio content is part of that push as well.If you are an Amazon Prime member, check if you are targeted for a free 30-day trial to Audible Premium Plus which will include 2 free audiobook credits.

According to The Wall Street Journal, Prime customers spend as much as double on purchases on to what non-Prime customers spend in a year. Amazon Prime has emerged as one of the key pillars of the company’s e-commerce and streaming businesses. It’s not particularly surprising that Amazon is adding more content to the Prime membership. Like with Prime Video, Amazon is letting members access exclusive, Audible-produced audio content such as Ponzi Supernova, a podcast detailing the crimes of financial criminal Bernie Madoff, which includes jailhouse interviews with Madoff himself. In addition to podcasts, Channels also includes access to audio versions of articles from major publications, comedy shows, short fiction, and more. Get Data Sheet, Fortune’s technology newsletter. Audible released the service in July, and is charging non-Prime members $4.95 each month to access the selection of podcasts. Prime members will also have free access to Amazon’s newly launched on-demand audio service from Audible, Channels, which provides ad-free podcasts and other audio content. With Tuesday’s news, Prime members will now able to stream a rotating selection of more than 50 audiobooks. Amazon has historically declined to reveal how many Prime members it has in the U.S., but has said publicly that it is in the “tens of millions.” Furthermore, 38% of American households are members, according to research from investment bank Cowen. According to a recent Consumer Intelligence Research Partners report, Prime has 54 million U.S. For $99 per year, Amazon Prime members can access and stream digital movies, TV shows, and Amazon’s original productions in addition to receiving free two-day shipping and one-hour delivery on certain orders.

Free audible with amazon prime