He was found dead inside his home in Dorset yesterday and his representatives say there was "no suspicious circumstances".
It comes just weeks after the beloved band's planned reunion to celebrate S Club 7's 25th anniversary.
A statement from Paul's family and bandmates reads: "It is with great sadness that we announce the unexpected passing of our beloved son and brother Paul Cattermole.
"Paul was found yesterday, 6th April 2023 at his home in Dorset and was pronounced dead later that afternoon.
"While the cause of death is currently unknown, Dorset Police has confirmed that there were no suspicious circumstances.
"Paul’s family, friends and fellow members of S Club request privacy at this time."
An insider says all of S Club 7's members are "in pieces" because of the tragic news.
"Hannah [Spearritt] and the rest of the gang broke down when told what happened," a management source told The Sun.
"No one can believe it. There is a real sense of horror and disbelief."
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