The 19-year-old Maza, who has become a key figure for Hertha despite their struggles, made 30 appearances this season, registering five goals and five assists.
His performances have not gone unnoticed, and with Hertha Berlin facing another year outside the Bundesliga, Leverkusen seized the opportunity to activate his release clause.
The Algerian international completed his medical at the BayArena over the weekend before signing a five-year contract that will keep him at the club until the summer of 2030.
The move is seen as a significant step in Maza's development, especially under the guidance of head coach Xabi Alonso, who has transformed Leverkusen into one of the most dynamic sides in Europe.
Speaking after his unveiling, Maza expressed his excitement at joining a club with continental ambitions.
"I want to prove myself on the big stage at a top European club. I'm really looking forward to Bayer 04, to the special close-knit atmosphere, and to a team that has impressed me greatly in recent years. Here in Leverkusen, I can continue to develop and win titles - that's what drives me," the midfielder told the club's media.
Leverkusen have already qualified for next season's UEFA Champions League, giving Maza the perfect platform to showcase his abilities at the highest level of club football.
Manchester United have reportedly made a bold move to sign Bayer Leverkusen's Jonathan Tah, sensing a chance to hijack the defender's expected transfer to Barcelona, according to Sky Germany.
Bayer Leverkusen's head coach Xabi Alonso firmly dismissed speculation about his future, reaffirming his focus on the team's upcoming Bundesliga match against Freiburg.
Tottenham Hotspur are reportedly eyeing deal for Bayer Leverkusen forward Victor Boniface.
Bayer Leverkusen's veteran defender Jonathan Tah has confirmed he will leave the club this summer, bringing an end to his decade-long spell at the BayArena.
