In a club statement,, external he said his decision to retire at the end of 2023 had given his body “time to heal” and he now felt he was “ready to contribute for a full season”.
Dragons coach Steve McNamara added: “After conversations with Sam, I am fully convinced he is mentally and physically ready to be a hugely influential player for us in 2025.
“He will undertake a vigorous pre-season, which I am certain will see him return to his very best form.
“He is a huge asset to our team with his ability and leadership.”
Tomkins, who joined Catalans at the start of 2019, won Super League’s Man of Steel award in 2012 during the first of his two spells with Wigan Warriors and again in 2021 with the Dragons.
He was on the winning side in three Super League Grand Finals, all with Wigan, while he has been on the losing side at Old Trafford with Catalans in 2021 and 2023.
At international level, he captained England at the most recent Rugby League World Cup in 2022, with Shaun Wane’s side exiting at the semi-final stage.