When a countdown appeared on the band's site, excited fans wondered whether the girls would be announcing the news of their return on October 19.
The surprise was ruined, however, when the band's new single, Something New, was leaked four days before the countdown reached zero.
Opting for plan b, the group decided to release their dance single for airplay from midday on October 16.
On the same day, a sneak peek at the video for their new track was released featuring the friends in orange tulip dresses strutting away from the camera.
And on Friday morning, the October date they were waiting for, the girls confirmed they will reunite for a 12-date arena tour and will be releasing a greatest hits album entitled Ten on November 26.
The girls have also taken up a new venture with the tour's official sponsor, Pandora, and have personally designed their own bracelets for the jewellery company.
The five bracelets, which reflect each of the band member's personalities, go on sale from October 19 in all Pandora stores nationwide.
Their new single will be available to buy on November 18.
Girls Aloud, who are returning after a three-year hiatus, were formed as part of early X Factor-style show Pop Stars: The Rivals in 2002.
The ladies were in direct competition with boy band One True Voice for the Christmas number one.
Girl power won the day, with their single Sound of the Underground pipping the boys to the post.
It paved the way for a stellar career, with the band racking up 20 consecutive UK Top 10 singles (including four number ones) and two UK number one albums.
They have also been nominated for four BRIT Awards, winning Best Single in 2009 for The Promise.