Alonso, 43, made the announcement during a press conference on Friday, stating that this weekend's fixture against Borussia Dortmund would be his final home match in charge at the BayArena.
"This week, the club and I agreed that these last two games will be my last as head coach," Alonso said. "Now is the right time to announce it."
Alonso departs having overseen one of the most successful periods in Bayer Leverkusen's history. Appointed in October 2022 with the club languishing near the bottom of the Bundesliga table, he engineered a rapid and sustained transformation. This season, under his leadership, Leverkusen clinched a domestic double and became the first side in Bundesliga history to complete a full league campaign undefeated.
Reflecting on his decision, Alonso emphasized timing and mutual respect between himself and the club.
"It's about moments in football," he said. "Choosing the right one can be the most difficult decision. I feel this moment is appropriate, and I am proud of what we've built together."
While Alonso declined to elaborate on his next move, his return to Real Madrid - where he spent five seasons as a player and won multiple titles, including the UEFA Champions League - appears imminent. According to multiple sources, he is the leading candidate to succeed Carlo Ancelotti, whose position at the Bernabeu has come under scrutiny following a disappointing campaign.
Ancelotti, despite winning LaLiga and the Champions League during his second spell with Madrid, has seen his side fall short this season in all major competitions, including early exits from the Copa del Rey and Champions League, and a likely league title loss to rivals Barcelona.
Alonso's managerial credentials have drawn considerable attention across Europe. Following his retirement as a player in 2017, he began his coaching career within Real Madrid's academy setup before moving on to manage Real Sociedad's B team. His tenure at Leverkusen, however, has elevated his status significantly, with his tactical acumen, leadership, and composure drawing praise from players and analysts alike.
"The players have given me so much," Alonso said. "We've had a great connection, and they believed in me from the start. That's why there's been such strong chemistry within the squad."
Alonso indicated that further details regarding his future would be disclosed only after the conclusion of the season.
"I've grown a great deal - as a coach and as a person," he added. "Once the season is complete and we've fulfilled our responsibilities, then it will be time to speak about what comes next."
For now, Leverkusen fans will look to bid farewell to a coach who not only revived their club but elevated it to unprecedented heights - and who now appears destined to return to one of football's grandest stages.