Eichhorn made history last August as the youngest player to start a Bundesliga 2 match, immediately displaying remarkable composure for a 16-year-old midfielder. He went on to make 17 appearances for Hertha during the 2025/26 campaign, scoring his first professional goal in a 2-1 win over Greuther Fürth in May.
"We are very happy we were able to convince Kennet Eichhorn of our approach. We were already in close contact with Kennet and his family a year ago, and even back then we formed a good bond. That was also always evident in this year's talks," said Leverkusen sporting director Simon Rolfes.
"Kennet shares our view that Bayer 04 offers the best conditions for him to develop into an absolute top player in the Bundesliga. The talks with our head coach Carles Martínez were also characterised by great agreement on footballing issues and mutual trust. With Kennet, we now have one of the best German talents in our ranks."
