The process of sharing playlists in Apple Music is generally pretty straightforward: You tap on the share button and a standard iOS Sharing Sheet comes up that allows you to copy a playlist link to your clipboard or send it out via text, email, or social media. Anybody with the link and iTunes 12.2 or iOS 8.4 or later can then simply click on it to see the content of the playlist in iTunes or the iOS Music app, and even save a reference to it in his or her own library. Playlists that you’ve shared are indicated by the word “Shared” when viewing them in the iOS Music app, although this distinction is less clear in iTunes.
However, what if you decide that you no longer want to share a playlist? While the option for sharing is pretty easy, the option to stop sharing is a little more hidden, but it’s still there. In the iOS Music app, you need to go into the playlist and tap the “Edit” button as you normally would to add, remove, or reorder tracks. If you then scroll up to the very top, you should see a switch labeled “Shared Playlist” — toggling this off and saving your changes will disable sharing for that playlist. Note that while the Music app shows this as a toggle switch option, it’s really not — once you turn it off, it disappears entirely, so it’s a rather odd use of that particular UI control.
iTunes 12.2 takes a slightly more intuitive approach, with a “Stop Sharing” option on the playlist menu that can be accessed from the ellipsis button to the right of the playlist title. Note that while this will disable sharing for the playlist, Apple Music doesn’t regenerate the sharing URL should you later decide to share the playlist again — so anybody who had the original link would still be able to access your playlist if you turn sharing back on. If you want to reshare the playlist and ensure former users can’t access it, your only option is to copy the tracks to a new playlist, delete the original playlist, and share the new one.