Speculation had been mounting about the future of the New Zealand international, but he has now committed his future to Justin Morgan’s side.
Webster, XX, said: “I am delighted to have sorted things out and I couldn’t be happier. I’m confident the club can challenge for honours and I want to be part of that.
“I have never settled for being second or third best. I want to be a winner and that’s why I was happy to sign the new deal.”
Webster is currently sidelined with a hip injury which could keep him out for up to three months.
He added: “I still think I can make the play-offs and the new contract has given me the incentive to make sure I do.
“I want to get the surgery out of the way and then go from there.”
Webster started his career at Melbourne but joined new NRL franchise Gold Coast in 2007, before moving to Rovers for the 2008 season.
Rovers coach Morgan said: “He has already shown he is one of best centres in the game and I believe there is a lot more to come from him. He is injured at the moment but I’m sure he will come back stronger.”