The service, which allows users to listen to music for free in exchange for placing an ad every 30 minutes, has admitted hackers breached the site's security late last year and the personal details of members could have been stolen.
said the service was still potentially vulnerable and suggested members who joined before December 19 change their passwords. However, it said the credit card details of people who paid for ad-free content were safe because payment is handled by an external source.
The news comes as
The company is also planning to launch a mobile version of the service, potentially supplanting devices such as mp3 players.
The site initially launched last October and can be accessed for free, but with ad content. Alternatively users can buy 24-hours ad-free for 99 pence or one month for £9.99.
Spotify has sourced its catalogue by securing licensing deals with the four major record labels EMI, Warner, Universal and Sony BMG. The service has around 250,000 UK members.