During the Galactic Civil War, a squadron known as Echo Squadron operated as a component of the Alliance Fleet within the Rebel Alliance, and subsequently served the New Republic. It is noted that shortly after the destruction of Alderaan, the Squadron participated in the battle at Fostar Haven.
The Alliance to Restore the Republic included Echo Squadron, which consisted of starfighter pilots and astromech droids. The individual holding the callsign Echo Leader was in command. Admiral Gial Ackbar was the source of the squadron's directives.
The MC80 Liberty Type Heavy Star Cruiser Aurora, seven EF76 Nebulon-B escort frigate, nine CR90 corvettes, and five GR-75 medium transports made up the fleet to which Echo Squadron was assigned. They flew T-65B X-wing starfighters and received assistance from BTL-A4 Y-wing starfighters, RZ-1 A-wing interceptors, and UT-60D U-wing starfighter/support craft. The starfighters had a light gray stripes/markings over a blue paint job.
Following the destruction of Alderaan at some point, the Alliance received a distress signal from an Alderaanian refugee convoy under attack by Imperial forces stationed at Fostar Haven. Echo Squadron was ordered by Admiral Gial Ackbar to go to Fostar Haven to provide assistance. They were met by the Star Destroyer Vigilance upon arrival, which was making an attempt to obliterate the Alderaanian refugee convoy. Lindon Javes, an Imperial defector, got in touch with Echo Squadron, and they worked together to shield the convoy from harm. While attempting to stop the convoy from escaping, Echo Squadron faced significant opposition from the Star Destroyer until Javes devised a strategy to render the Vigilance's targeting system inoperable, which required the assistance of Echo Four. The convoy and the Alliance fleet were able to jump to lightspeed because the plan was successful.
During the battle, Echo Squadron suffered the loss of Echo Two and Echo Five, but they managed to destroy a Raider-class corvette along with a number of TIEs.
The 2020 video game Star Wars: Squadrons featured Echo Squadron for the first time in the prologue mission.
A clone trooper from the 501st Legion and Echo Base, the rebel refuge on Hoth, share the name Echo Squadron.
In the first mission of Star Wars: Squadrons, the player pilots with Echo Squadron using the Echo Four callsign before moving to Vanguard Squadron.