The 25-year-old right-back returned to a familiar environment after making 38 competitive appearances for the German champions since his move in January 2024.
Boey initially joined Bayern from Galatasaray for 30 million euros and remains under contract in Munich until June 2028. During his time with the Bundesliga giants, he scored one goal and registered five assists, contributing to their 2024-2025 Bundesliga title and the 2025 Franz Beckenbauer Supercup success.
Confirming the deal, Bayern board member for sport Max Eberl said the move offered the defender an important opportunity to play regularly. "Sacha knows Galatasaray from before he moved to us and won't need long to settle back into that familiar environment," Eberl explained.
"He can get playing time at the highest level in the Champions League play-offs against Juventus and in the Super Lig title race, which will be very good for his development."
Boey has struggled to secure a consistent starting role this season despite featuring in several matches across competitions. A return to Istanbul gives him the chance to regain rhythm and confidence while helping Galatasaray compete domestically and in Europe.
The loan move represented a strategic decision for both clubs. Bayern gained flexibility within their squad, while Galatasaray strengthened their defensive options with a player already familiar with their system and supporters. If the option to buy is activated, the Turkish champions could secure a permanent reunion with a full-back who previously impressed during his first spell at the club.
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