Önsoy has written music for award-winning films, featured at such festivals as San Sebastian Film Festival, IDFA Documentary Festival, Palm Springs and Cannes Film Festival. His recent works include the short, Mechul (Cannes Film Festival 2017), Dutch TV Documentary Four Winters of Theo van den Boogaard and the IDFA Audience Prize Winner, Netherlands Film Festival Golden Calf for Best Documentary Feature nominated film, Naziha's Spring. Önsoy has also written music for many shorts and animations, including the film entitled, Onno the Oblivious, which won the 'Orona Award' for 'The Most Cutting Edge Film' at the 62nd San Sebastian Film Festival, and English National Opera commissioned award-winning animation, Leonor.
Önsoy received a Masters in Composition for Screen from the Royal College of Music in London (Soirée d'Or Scholar supported by a Clifton Parker Award), a Bachelor’s in Jazz Piano and a Master’s in Composing for Film from the Conservatory of Amsterdam. He has had his concert works performed in various venues, including the Amsterdam Grachten Festival. As a performer he has participated at the Tetouan 13th International Oud Festival in Morrocco, as well as the Istanbul International Improvisation Festival.
Through the years Eren Önsoy has become well-versed in many different musical languages, including jazz, contemporary music, and electronica. He is currently writing the score for his third feature film, Nocturne, directed by Viktor van der Valk.