Lewis has become a multi-platinum selling artist and three time Grammy Award nominee. She has released one album to date, Spirit, in 2007. It became the fastest-selling debut album and the biggest seller of 2007 in both the UK and Republic of Ireland, and made Lewis the first British solo artist to top the Billboard 200 with a debut album. Her second album, Echo, is due for release in November 2009.

Lewis's debut single "A Moment Like This" became the fastest selling UK single after being downloaded over 50,000 times within thirty minutes of its release. Her second single, "Bleeding Love", reached number one positions in over thirty singles charts around the world. In November 2008 she set a record in the UK for the fastest selling download-only release with her cover version of the Snow Patrol song "Run" which sold 69,244 copies in two days.