Easily transfer all your playlists curated over the years from your iTunes Music app to Spotify.
You can import your all your playlists by exporting the entire library or just a single playlist.
Instructions
Launch iTunes Music on your desktop.
Navigate to File → Library → Export Library…
Save it in a conveninent location (ie Desktop or Downloads folder).
Link your Spotify account (on this page).
Upload the exported iTunes Library XML file (on this page).
Done! Open Spotify to see your imported playlists.