The group had bubblegum pop hits like 1999 debut single Bring It All Back, as well as Reach and Don't Stop Movin'.
All seven original members, including later solo star Rachel Stevens, will hit the road again together for the first time since 2015.
Stevens said it will be "special" to get the chance to bring their "joyful and positive" music back around.
"I think where we are in the world right now, we just want to get up there and bring some joy and positivity," said the singer at a press conference on Tuesday morning.
