Jones has agreed to join Salford after leaving rugby union.
The 22-year old back-rower, who can also play in the centres, switched codes and left Saints last year to sign for Exeter.
But the move did not work out for Jones and he has returned to Super League.
He made his debut for St Helens in 2012. Jones managed 21 tries in 64 appearances for the club, playing in Saints’ 2014 grand final win.