The club's confirmed the deal will work as a loan, with Gildart to join the Roosters for the remainder of the season, before returning to the Tigers on November 1 ahead of pre-season training kicking off for the 2023 campaign.
Gildart has struggled for game time at the Tigers this season, with his adaptations from the English Super League to the NRL having plenty of bumps in the road.
The Englishman was touted as a big signing for the Tigers, but between a lack of form and a handful of injuries, he has played just eight games, and scored only a single try.
His last outing for the club in the NRL was during Round 9, when he scored said try in a loss to the Manly Sea Eagles at Brookvale. The game doubled as his likely best game in the competition, making three line breaks and five tackle busts.
The three-Test English player has one year remaining on his deal with the Tigers and will likely need to improve if he wants to remain in the competition beyond the end of 2023.
Tigers CEO Justin Pascoe said the move works for Gildart, and for the Tigers on a strategic level.
“This works for Oliver, and it works for us as well. So strategically, it makes sense," Pascoe said.
"Oliver will return to us after this short loan and begin preparing for 2023.”
Gildart will be eligible for selection this week for the Roosters, although would need to force his way past Joseph Manu or Paul Momirovski to be named in the 17 as the tri-colours battle for a finals spot.