T'ra seldom spoke of her youth, and hence very little is known of her life, other than that she joined the Jedi Order and gained the rank of Jedi Master centuries before the fall of the Republic. However, it is known that she was involved in the training of Jedi Master Mace Windu, while he was still a Jedi apprentice, but the extent of training and whether it was an official Padawan-Master relationship is unknown.
Prior to the Stark Hyperspace War, she was appointed Jedi watchman of the sector of space including Kiffu and Kiffex, after her close friend Tholme stepped down from that post, so he could take Quinlan Vos as his Padawan. Later, Master Saa assisted Quinlan Vos in defeating Volfe Karkko's Anzati uprising on Kiffex. Saa avoided detection in tree form and when Quinlan Vos was captured by feral Anzati she freed him and helped him destroy his captures.
At some point during their association, Masters Tra and Tholme fell in love, but managed, in Tholme's opinion, to avoid the selfishness, jealousy, and attachment that so often came with love; meaning that the pair believed that they had managed to find a way to love in a way that avoided the lure of the dark side. At the same time, the pair recognized that T'ra was centuries older than Tholme, and accepted that T'ra would likely outlive him.
Along with Masters Yoda and Fay, Jedi Master T'ra Saa was among the very oldest Jedi to fight in the Clone Wars, being at least several hundred years old. Saa was a combatant in the opening battle of the war, the Battle of Geonosis, and fought as part of Mace Windu's strike team. Indeed, T'ra was among the few Jedi to survive that devastating battle.
Later, Jedi Masters Saa, Tholme, An'ya Kuro, Kit Fisto and Jedi Knight Aayla Secura, were assigned the mission of investigating Confederacy raids on Republic supply ships near the Corellian Trade Spine. The Jedi task force discovered that the raiders' base was located on Devaron, after T'ra received information from her old friend Senator Elsah indicating that this was so. However, the senator was killed by failed Jedi Aurra Sing before she could reveal the name of the traitor who was aiding the Separatists locate the Republic supply ships.
While Masters Saa and Fisto remained in orbit around the planet, Tholme led the strike team to the surface of Devaron so as to investigate the late Elsah's claims. Tholme's task force disguised themselves, with Secura acting as a rich Twi'lek's daughter, and the remainder of the team as her servants, all the while staying with Devaron Senator Vien'sai'Malloc. Kuro and Tholme attempted to discover the Separatist base, only to fall into the trap of Aurra Sing, who had been assisted by Senator Vien'sai'Malloc, who was revealed as the traitor. However, Aayla Secura apprehended both the Senator and Aurra Sing, saving the two more experienced Jedi.
After Master Quinlan Vos, formerly Tholme's apprentice, infiltrated the Confederacy by feigning a fall to the dark side, fears began to arise on the Jedi Council as to whether Vos continued to serve the Republic or truly had fallen under the sway of Count Dooku's dark influence. T'ra supported Tholme during his communication with Masters Yoda and Windu, as he informed them that Vos had failed to contact him as designated.
During the Battle of Null, T'ra Saa acted as ranking member of the Republic forces stationed there. While using the force to heal injured troops and Jedi, Saa and Jedi Knight Barriss Offee were unexpectedly attacked by bounty hunters working on behalf of the Crimson Nova, who had placed significant bounties on the heads of Jedi. During the fighting vast fires raged towards the camp, while Saa's lightsaber was knocked from her hand and stolen by a fleeing bounty hunter. To protect the injured, Saa was compelled to put on a masterly display of her skills with the Force, to down trees and protect against the approaching blaze. However, Saa was grievously injured, saved only by the timely arrival of Master Windu, who had her placed in a bacta tank to recover. Windu then led a mission to the Rig, which led to destruction of the Crimson Nova, during which he recovered Saa's lightsaber and subsequently returned to her.
T'ra was on Nar Shaddaa with Tholme and the pregnant Khaleen Hentz in the final days of the Clone Wars, where they evaded Order 66. After Order 66 all three fled Nar Shaddaa and hid on Kashyyyk along with Quinlan Vos, who was stationed on Kashyyyk during the Clone Wars.
Some time after the rise of the Galactic Empire, Tholme passed away. T'ra Saa, was later said to have taken root at the site of Tholme's funeral pyre on Anzat. In the aftermath of the Sith-Imperial War, in which the New Jedi Order, that had been restored following the defeat of the Empire and Saa subsequently joined, was nearly destroyed, T'ra Saa became a member of the Jedi High Council alongside Masters Tili Qua and K'Kruhk.
Having taken refuge at the Hidden Temple, Master Saa and the Council were present when Cade Skywalker and Emperor Roan Fel's Imperial delegation arrived seeking refuge. T'ra, along with the rest of the Council, listened to Princess Marasiah Fel's offer for the Order to join forces with Roan Fel and the truth that Fel was not responsible for the war or the Massacre at Ossus. T'ra saw the truth in her words but believed the Jedi needed to regroup and increase in numbers before confronting the Sith again. Master Saa refused to believe Cade when he said that Darth Krayt was really A'Sharad Hett, but K'Kruhk believed it, saying that there was always a darkness in Hett and that the Clone Wars had changed many Jedi.
At this point, Cade suggested assassinating Krayt. Master Saa was stunned by the suggestion, saying that the Jedi hold all life sacred, and to actively seek out and destroy life was not the Jedi way. Despite this, the Council agreed to discuss it. They spent the night discussing Cade's suggestion with Nat Skywalker. T'ra said that they had to help the Mon Calamari fight against the genocide the Sith were wreaking on them, but was concerned because they didn't have enough Knights and Masters at the Temple, and was worried if the Galaxy would be given to the Sith if they acted now. After long deliberation and meditation, Masters Qua, K'Kruhk and Saa unanimously decreed that the Jedi would play no part in the assassination of Krayt; they felt it would be wiser to give the Order time to grow stronger, while the Sith undermined each other.
However, Cade continued with his plan to assassinate Krayt despite the Council's decision; the plan ending with the Dark Lord's death, though it was his most trust advisor Darth Wyyrlok II who ultimately murdered and replaced him as the new Dark Lord. Subsequently, Cade asked his companion Jedi Knight Shado Vao, who was returning to the Temple, to inform the Council that Krayt was dead.