Washington was born in Harlesden, north-west London on 27 October 1978 and always had a big passion for music and would listen regularly to her parents' music collection as a child; this is where she believes her ability to sing and rap came from. Washington's career began in 1999, when she met Alesha Dixon and they joined "Dance Attic" (a popular dance class school in Fulham, west London), soon becoming a duo. In 2000, when both Alesha and Sabrina were auditioning, they met with Su-Elise Nash and formed a trio. They were signed to Inferno Records with the addition of a new member, Zena McNally, and became the popular UK garage/R&B girl group, Mis-Teeq. However, after the release of their debut single "Why?", Zena McNally left the band to pursue her own solo career, and Mis-Teeq were signed to another record deal with Telstar Records.