"Sheri's going to move to Toulon this summer," Steve Diamond, Sale's executive director of sport, confirmed.
"It's his decision. He's been a loyal member of the club for a long time but he feels that he's best suited for the next two or three years to try his hand by playing over in France."
Sheridan, who has been with Sale nine years and has 40 England caps, was forced out of last year's World Cup when he injured his shoulder in the opener against Argentina.
His international days could now be numbered after his decision to move abroad with the RFU having a strict policy of only selecting home-based players except in exceptional circumstances.