The trials and tribulations of the Kitauji High School concert band will return in Sound! Euphonium the Movie ~Oath of the Finale~ (Gekijouban Hibike! Euphonium ~Chikai no Finale~). The original anime film will open in Japanese theatres in spring 2019.
— アニメ「響け！ユーフォニアム」公式 (@anime_eupho) June 3, 2018
The film will follow Kumiko Omae as a third-year student mentoring the incoming class of juniors. Other details are thin, but Tatsuya Ishihara (Sound! Euphonium season 1 and 2) will direct the film and Tomoyo Kurosawa will reprise her role as Kumiko.