The former Lions centre had requested to be released from his contract with the Ospreys to join the English outfit but the high-profile move has proved shortlived.
"Gavin Henson has asked to be released from his contract with Saracens with immediate effect," read a Saracens statement.
"The club has agreed to this request."
"We wish Gavin all the best for the future as he continues his return to the highest level of the game," added chairman Nigel Wray.
Henson made just one start for Saracens before picking up a calf injury in the Heineken Cup defeat to Leinster last month.
He wasn't considered for a place in the Wales squad for the Six Nations because of that injury setback but he could be called up for the latter stages of the tournament if he proves his fitness to Warren Gatland.
Although neither party have yet confirmed the move, Henson looks set to join Jonny Wilkinson at Toulon immediately on a two-and-a-half year deal up until the summer of 2013.
It is thought that Toulon have agreed to Henson's request to be allowed to attend Wales training if he is called up for the Six Nations or in the lead up to the 2011 World Cup.
Toulon, who recently qualified for the quarter-finals of the Heineken Cup after knocking out Munster and Henson's former employers the Ospreys, will be without Wilkinson for the duration of the Six Nations, while Argentinean star Felipe Contepomi is currently out injured.
That leaves Philippe Saint Andre short of cover at fly-half - the position Henson admitted he wanted to play when he initially joined Sarries.