Campbell told Titans officials on Friday he would stay take up a five-year extension, setting himself up to be a one-club player and a cornerstone of the Josh Hannay era.
AAP understands Campbell stood to earn significantly more money as the Bears' inaugural halfback, after being offered a deal in vicinity of $6 million over five years.
But the 25-year-old has opted not to leave the club where his father Preston is a favourite and foundation player in their first season in 2007.
"The Titans mean everything to me. They've done a lot for me and my family, and I'm stoked to extend my time here for another five years," Campbell said.
"I absolutely love this club and always have since 2007, so I'm honoured to be able to keep playing for the fans who have backed me and my family since day one.
"I'm really excited about what we're building under Josh."
Had Campbell signed with the Bears, he would have become one of their biggest-name signings for their first season in 2027.
The likes of Herbie Farnworth, Harry Grant and Josh Addo-Carr have also been taken off the market since the end of the season, and could have been potential targets.
The Bears have also shown an interest in Titans skipper Tino Fa'asuamaleaui, while South Sydney forward Keaon Koloamatangi is understood to be a target.
Campbell's signature comes after Titans forward Beau Fermor knocked back Perth to stay with Gold Coast this week, in two big wins for the Titans and Hannay.
Hannay almost has a blank canvas to work with such is the fluidity of his roster, with David Fifita headlining a long list of exits from the club in recent months.
Fermor on Friday said conversations with Hannay in recent months had convinced him to remain at the Titans.
"Having discussions with Josh over the off season and seeing the direction he wants to head the club in was something I could really get on board with," Fermor said.Â
"There has been a lot of good change around the joint over the off-season that probably isn't seen in the public eye but we can all see it here."
Fermor has previously worked with Hannay in his role as an assistant in Queensland State of Origin camp.
"I really like where he thinks my game can go personally and where he can take our team as well," he said.
Hannay's next roster challenge will be convincing Fa'asuamaleaui to stay, with the Australian Test prop signed until 2033 but with an option to leave next year.
The front-rower has told AAP his preference is to remain a Titan, but he wants to see that he can achieve success at the club before committing.