At the age of twenty, Stevens became a member of the British pop group S Club 7, which were a BRIT Award-winning British pop group created by former Spice Girls manager Simon Fuller. The group rose to fame via their own BBC television programme and by selling 16 million records worldwide and launching four number one hit singles in the United Kingdom. S Club eventually split up in 2003.

After S Club were disbanded, Stevens signed a £1.5 million ($2.3 million) solo four-album deal with Polydor Records and re-signed with Fuller. Her first solo single, written by Cathy Dennis (who has also written for Britney Spears and Kylie Minogue) and produced by Bloodshy & Avant, “Sweet Dreams My LA Ex”, was released in September 2003. Stevens’s debut solo album, Funky Dory was released later that month. The album was a minor hit, reaching number nine on the UK albums chart. Although the album was not a huge commercial success, it did gain praise from pop critics. That December, the album’s title track, “Funky Dory” was released as the second single.The song was given mixed reviews by pop-critics with some calling it “musically better than “Sweet Dreams My LA Ex” with a hybrid of pop, Latin and even a hint of jazz infusion” but not a good choice as a single as it lacked anything special and different, as it did not live up to Stevens’s previous single.

In July 2004, Stevens released a brand new song, “Some Girls” which was produced by Richard X.The song became a hit across Europe, and reached number two in the UK. All profits from the song went to the BBC Sport Relief charity. Due to the success of “Some Girls”, Funky Dory was re-released to include “Some Girls” and another new track, a cover of Andrea True Connection’s “More More More”. “More More More” peaked at number three in the UK, giving Stevens her third top ten solo single in the UK. At this point, Stevens stepped up promotion, inadvertently earning herself a Guinness World Record for “Most Public Appearances by a Pop Star in 24 Hours in Different Cities” (Seven on 8 September-9 September 2004).

In late 2004, Stevens began working on her second solo album with producers and songwriters Richard X, Alexis Strum, and Xenomania. The following March she released the first single from her upcoming album, “Negotiate With Love”. The song was hit in the UK, reaching the top ten.”Negotiate with Love” was followed-up by the song “So Good”, which was released in July and was another success when it peaked at number ten in the UK. The album, “Come and Get It” was later released in October 2005, peaking at number 28 in the UK. The last single released from Come And Get It was “I Said Never Again (But Here We Are)”, released in October 2005 the song peaked at number twelve in the UK. Two years after the album’s release, The Guardian placed it in their article “1000 Albums You Must Hear Before You Die” list.

After some time out of the spotlight, Rachel decided to take part in the hit show “Stricltly Come Dancing.” In August 2008, it was announced that Stevens would take part in the 2008 series of Strictly Come Dancing, which started on 20 September. She was partnered with professional dancer Vincent Simone, and together they hold the record for the most perfect 10s ever achieved in any series of Strictly Come Dancing, thus beating out other contestants including 2007 winner Alesha Dixon and 2008 winner Tom Chambers. Rachel ended up finishing second place in the competition. Shortly after Rachel wed her childhood sweetheart, and gave birth to the couples first child Amelie.