The Daily Mail report that the Sale Sharks prop, who returned from last year's World Cup with a serious shoulder injury,
is set to link up with fellow former tourist Jonny Wilkinson at Stade Felix Mayol.
Sheridan rejected a similar move last year, to ensure his place at the global gathering, but his current contract with Sale is due to expire in the summer and he jetted to the south of France to discuss a lucrative deal this week.
The powerhouse prop, who has made 11 appearances for the Lions, allegedly met with coach Bernard Laporte during the trip.
Any decision to move to the Continent would effectively end his international ambitions with the RFU advising against the selection of overseas-based players.
Meanwhile the Daily Telegraph report Sheridan could be joined at Toulon by two more Aviva Premiership stars with London Irish duo Delon Armitage and Nick Kennedy linked to the big-spending club.
They claim Kennedy has already agreed to a three-year deal while Armitage's omission from England's Elite Player Squad could lead to him joining his brother Steffan at Toulon