The Legacy System is a secondary leveling system added in Patch 1.2.0. Leveling is achieved via a range of activities, with a common Legacy experience bar shared between all characters participating in the player's Legacy.
The features of the Legacy system include: Family Tree, Global Unlocks and Character Perks.
 Family Tree
The Family Tree allows the player to create a relationship structure between characters on the same server. There are six different relationship options: Spouse, Rival, Ally, Adopted Child, Child and Sibling.
- Only 1 spouse per character.
- Only 2 ally, rival, or spouse relationships per character.
- There is no limit to the number of children a character can have.
 Global Unlocks
Global Unlocks are benefits that affect all characters in the player's Legacy. As the player progresses a class, they will grant other characters an extra emote ability, add the class' buff effect to the buffs of other classes, and finally unlock a Heroic Ability which can be used during Heroic Moment. Also, completing the conversation options for a companion will grant a +10 bonus to Presence on all characters and add a bonus to a stat depending on which companion is active.
 Class Buff
Once a character finishes Chapter 2, he adds his class buff effect to the buffs of all other characters in the legacy. The unlock is shared across factions, but always the faction specific buff applies; i.e. when a Smuggler unlocks his buff, a Jedi Knight will get the smuggler's Lucky Shots added to their own buff, while a Sith Marauder will get Coordination.
- Jedi Consular / Sith Inquisitor: Force Valor / Mark of Power
- Increases the target's Strength, Aim, Willpower and Cunning by 5% and internal and elemental damage reduction by 10% for 60 minutes. If the target is a party member, all other party members are also affected.
- Jedi Knight / Sith Warrior: Force Might / Unnatural Might
- Increases the target's melee, ranged, Force and tech bonus damage and healing by 5% for 60 minutes. If the target is a party member, all other party members are also affected.
- Smuggler / Imperial Agent: Lucky Shots / Coordination
- Increases the target's critical hit chance by 5% for 60 minutes. If the target is a party member, all other party members are also affected.
- Trooper / Bounty Hunter: Fortification / Hunter's Boon
- Increases the target's Endurance by 5% for 60 minutes. If the target is a party member, all other party members are also affected.
 Heroic Abilities
By completing the story of a specific class, the player unlocks one outstanding ability of that class for all other characters in the same legacy. Heroic abilities can be used only during a Heroic Moment:
- Bounty Hunter: Flamethrower
- Imperial Agent: Orbital Strike
- Jedi Consular: Project
- Jedi Knight: Force Sweep
- Sith Inquisitor: Lightning Storm
- Sith Warrior: Force Choke
- Smuggler: Dirty Kick
- Trooper: Sticky Grenade
The player can unlock these by either leveling a character of that species to 50 or by spending 1,500,000 with Legacy level 5. Unlocking the Human species grants +100 Presence to all characters. Unlocking other species allows the player to use that species for any future characters they create.
These Unlocks cover a range of benefits. Some are tied to specific requirements while others can be simply purchased. The Ship Unlocks grants access to a number of conveniences such as a repair droid, mailbox, Galactic Trade Network access and training dummies on the player's ship. Valor Unlocks grant unarmed combat moves and can be awarded by achieving a certain valor rank or via purchasing them. Convenience Unlocks include benefits such as reducing the cooldown on the player's Emergency Fleet Pass, Quick Travel or granting a Rocket Boost ability (which works similarly to the Sith Sorcerer's Force Speed). Lastly, the Social Unlocks grant a number of emotes, which can be unlocked upon reaching a certain Social rank or via purchase with credits.
The Unlocks can be seen below within each subcategory.
 Character Perks
Character Perks are benefits that apply only to the character they are purchased on. They were added in Patch 1.3.0 and are grouped into Advancement, Travel, Companion and Convenience.
- Advancement: Five different perks with five levels each, which offer increases in experience earned for warzones, flashpoints, space missions, class missions and exploration. The first level of these perks offers a 2% increase, with each following level increasing by 2%.
- Companion: Four perks that include granting increased affection gains from gifts, increased affection gains from conversations, increased chance for an augmented item when crafting and decreasing the time taken to sell junk items.
- Convenience: Allows the player to deploy a field repair droid or mail droid. The third perk allows the player to reassign skill points while in the field.
- Travel: Includes perks that allow direct travel to the player's capital world, Outlaw's Den, fleet vanguard vessel or the Black Hole. These perks share the same cooldown. There is also perks that allow the player to acquire each level of speeder training earlier than normal (for example, speeder piloting I can be acquired at level 10).
 Unlocking & gaining levels
Legacy is unlocked after completing Chapter 1 of the player's class quest line. Once unlocked the player will receive this in-game mail:
- From: Star Wars The Old Republic
- Subject: Your Legacy is now unlocked!
- You've now unlocked your legacy. For now, you can choose a unique last name that is shared across all of your characters. In the future, the legacy system will offer even more benefits to all of the characters in your legacy!
At that time the player is able to pick a Legacy name which is shared by subsequent characters on the same server.
Legacy experience is gained while defeating enemies, doing warzones, missions etc.
Rate of gain is approximately 18% of XP gain.
- Level 1: XXX,XXX XP
- Level 2: 241,000 XP
- Level 3: 242,000 XP
- Level 4:
- Level 5: 244,000 XP
- Patch 1.3.7 (5 Sep 2012): Legacy names are no longer unique. New Legacies that are created are now able to use a name that is already in use on the server. All players will be able to rename their Legacies once, at no cost, in a future update.
- Patch 1.2.0 (12 Apr 2012): Added