England fly-half George Ford will join Sale ahead of the 2022-23 Gallagher Premiership season.
The 28-year-old, capped by England on 77 occasions, has signed a three-year deal.
Ford, who returned to Leicester in 2017, will now leave Welford Road for a second time, having previously joined Bath in 2013.
Following the announcement, Ford, who elected against taking up an option to stay with the Tigers, said: “It has been the most difficult decision of my career.
“I am proud and grateful to represent this great club at Leicester and I will give my all for the rest of my time at Tigers.”
In a separate statement posted to the Sharks’ website, Oldham-born Ford added: “I’m excited about what the future holds – playing rugby in the North West, representing the club where I am from and helping drive Sale Sharks forward.”
Ford made his debut for England seven years ago before playing key roles in the Red Rose’s Grand Slam triumph and run to the World Cup final in 2016 and 2019 respectively.
However, he was overlooked by Eddie Jones for this year’s autumn internationals.
Leicester top the Premiership after eight wins from eight matches, with Sale 20 points adrift in eighth.
Sharks director of rugby Alex Sanderson said: “George Ford is world class – one of the very best fly-halves in the game over the past five years.
“This season he’s probably playing the best rugby of his career, so we’re getting him at the right time.
“I met him twice and we had the chance to show him around the ground and the fact that he’s taken this decision, in the form that he’s in, with Leicester doing so well, tells me that he believes in the ambition of this club, and in the culture that we’re building.
“He’s a northerner and his heart is very much in this area. He’s been away for some years now, but he’s coming back to his spiritual home. His family is hugely important to him and I know that his life outside rugby has played a part in this move.
“The exciting thing for me is that he’s 28 years old and he’s coming here in the form of his life. We aspire to be a major force in the Premiership and in Europe too and we’ve got one of the world’s best fly-halves in his pomp.
“It’s a massive boost for the club and it’s a big indication of what we’re all about and where we’re trying to get to.”
Ford made his first appearance for the Tigers in 2009 before winning the Premiership title four years later and then moving to Bath. He re-joined Leicester in 2017 and is the league’s top scorer this season.