The 'Superstar' singer, who parted ways with EMI in 2007, signed the deal live on UStream watched by fans.
In her management's offices, Jamelia said it was a "very exciting day for me" and added that she "wanted to share it with my fans".
The 29-year-old was emotional as she signed the deal in front of the management team and her two children. Who the deal is with remains unknown.
"Obviously this is really really exciting for me," she said. "Let the games begin!"
Last month the singer confirmed that she would shoot a video for her new single as soon as the deal was signed.
In an interview with DS last year, Jamelia said work on her new album had been going "absolutely amazing".