The Verge claims that the Swedish firm is holding talks with its record label partners to thrash out a deal to expand its free service.
Spotify is said to be keen to overhaul its agreements with Warner Music, Sony and Universal in the hope of reducing the amount it pays per song streamed and bringing free playback to mobile devices.
The firm already offers a free mobile streaming service in the US, but the terms of its existing licensing agreements in the UK state that it must be offered as part of a premium package.
Spotify faces increased competition in the music streaming sector, with the relaunched MySpace offering a similar service and Deezer gaining ground in the UK thanks to a subscription bundle with EE's 4G packages.
At present, UK subscribers can only gain access to mobile streaming by signing up to a £9.99-per-month account with Spotify.