The six times capped outside half joined the PRO12 champions from the Cardiff Blues in 2016 and has made 34 appearances for the Llanelli based region.
“I am delighted to be extending my stay at Parc y Scarlets with a new contract,” said Patchell. “I feel that my game has developed since moving here in the summer of 2016, and look forward to continuing that development for the next few years.
“Working with Wayne (Pivac) and his coaching staff was a big part of moving west and so I am delighted that they have also renewed their contracts. A promising start in the league has put us in a good position looking ahead to the festive derbies and I’m very much looking forwards to getting back to work with the rest of the squad and trying to develop our game further over the coming weeks and months.”
He started all of his 21 competitive games in his debut season at the region and to date has amassed 274 points. The 24 year-old made his home international debut at the Principality Stadium on Saturday.
“We’re delighted to confirm that Rhys has committed his future to the Scarlets,” said Pivac. “He’s been very good for us over the last couple of years and you can see that the move has been a success. He’s not the finished product, he knows that, but he’s a diligent worker and you’ll continue to see him develop.”
Meanwhile Scarlets scrum half Aled Davies will join the Ospreys next season on a two-year deal. Davies, who has five caps, started in Wales’ win over South Africa on the last Saturday.
“It’s been an incredibly hard decision to leave my boyhood club at the Scarlets where I’ve had a fantastic nine years at the club and leave many good friends,” said Davies.
“However, having sat down a few times with [head coach] Steve Tandy, it was clear that moving to the Ospreys was the correct rugby move for me and will allow me to develop further as a player. I believe the Ospreys gameplan will suit my style of play.”