No! Spotify users cannot directly save songs from Spotify to a USB drive. Spotify's music files are encrypted and can only be played within the app. While Premium users can download songs for offline listening, these files are stored within the app and cannot be exported or transferred to external storage devices such as USB drives. But it's not that difficult. All we need is a converter and a USB to transfer Spotify to USB.
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How to Transfer Spotify Music to USB?
You can transfer music and playlists from Spotify to USB for car playback by using NoteCable Spotify Music Converter.