When you play a song on Spotify, it uses some of your hard drive space to cache that file for faster playing later. Here's how to clear that cache if you need some extra disk space.
By default, Spotify limits its cache to 10 per cent of your free space, which means the default setting should be OK — but if you've changed it, you could run into disk space problems. All you need to do is delete the files in the following folder (for your platform):
If Spotify's automatic cache is too small for you, you can change it in the preferences, but be sure to clear it out if you start reaching the end of your hard disk!
Clear Spotify Cache [Make Tech Easier]