The 21-year-old made the surprise loan move to Chelsea after their failed attempt to sign now Tottenham star Xavi Simons last summer.
Buonanotte made just eight appearances across all competitions for the Blues, scoring once before returning to Brighton in January.
He was then shipped out on loan once again, this time to Leeds United, where he featured even less, with just four appearances.
Brighton have no confirmed that Buonanotte has once against been shipped out on loan, joining Spanish side Elche for the 2026-27 season.
Speaking to the club’s website, Sporting director Mike Cave said, “Facundo is a talented young player who has continued to develop since joining the club. This loan gives him the opportunity to play regular football in one of Europe’s top leagues.
“We believe this move will provide an excellent environment for him to gain further experience, and we’ll continue to monitor his progress closely throughout the season.“