News of Bayer Leverkusen approaching Tillman broke last week, following the Werkself's sale of Florian Wirtz to Liverpool for a British record fee.
Reliable reports, including those from Eindhoven Dagblad's Rik Elfrink and German newspaper Bild, indicate that the 23-year-old German-American has agreed to a five-year contract offer from Bayer Leverkusen, and the clubs are now in "advanced negotiations" for the €35 million-rated Tillman.
Tillman, a graduate of the Bayern Munich academy, joined PSV on loan from the Bavarian giants in 2023 before permanently moving to Eindhoven in the summer of 2024 for €12 million.
With PSV, Tillman impressed mightily with 19 goal contributions in his debut Eredivisie season. Last season, the attacking midfielder missed time with an injury, but still played a massive part in PSV's second-straight title run with 12 league goals. In total, the 23-year-old has scored 25 goals and assisted a further 16 in 73 games.
The American international is currently active at the Gold Cup in the United States, where he's scored three goals in as many games.
Tillman is under contract at PSV until 2028.