I have subscribed to Spotify Premium now but what happens to my playlists when the subscription expires?
Even if the Spotify Premium service expires you will still own your account and your playlists. However, you will lose the ability to make them available offline on your computer and mobile phone. If you already have offline tracks on any devices, these will disappear and you will have to re-sync the tracks for offline use next time you become a Premium member. Still, you will be able to listen to these same playlists using the free service, however only with an internet connection.