The quintet, who soared to fame on Popstars: The Rivals in 2002, are still four years off their milestone birthday.
But Cheryl, 34, is said to have put plans in motion to get back together with Kimberley Walsh, Nicola Roberts, Nadine Coyle and Sarah Harding.
They previously parted ways in 2013, with Cheryl only still in regular contact with Nicola and Kimberley.
The Sun alleges that the star recently reached out to Sarah, and they are now back in regular contact too.
The chart-topper is also working on her own new solo music; her first since her 2014 album Only Human.
This new rumour comes just days after Nadine pulled the plug on her first headline solo tour.
The entirety of the jaunt was scrapped, much to fans’ disappointment – although she has since joined the line-up for several festivals over the summer, such as Mighty Hoopla and Manchester Pride.
She wrote on her website: “Hi guys, I am so sad to say I’m not able to do the tour at this time.
“I am so sorry and really wish things were different but for many reasons it is not meant to be.”
She added: “You deserve the best show possible and with such big venues and very little dates it was becoming impossible to achieve what we had wanted to do.
“Everything is a lesson & this is definitely one for me. Thank you for your continued love & support!!!”
It was only last month that Kimberley revealed to The Sun Online that she was unlikely to reform with the group, who had a string of Top 10 hits between 2002 and 2012.
“I’m closest to Nicola and Cheryl now and I do see a lot more of them,” she said.
“I do still speak to the others, but a bit more like you just check in with people that you work with, I guess.
“It’s a different chapter in our lives now. We’ve got kids and things move on don’t they?”
Nadine told ITV’s Lorraine in February that she would never rule out further work with her ex-bandmates.
“I love Girls Aloud. I’ve always had so much fun and really had a great time,” she said.
“I would never, ever rule it out [a reunion]. We’ll see what happens and I’m looking forward to seeing the Spice Girls thing!”