Geof Holbrook was born in Guelph, Ontario in 1978, and began his musical studies in piano and violin. His first compositions were for a jazz/funk band with which he played guitar, keyboards, and trumpet. In 1998, Holbrook enrolled in McGill University to study composition, where he spent a year studying with Alcides Lanza and then studied with Denys Bouliane.

His compositions have been performed in Canada, the United States, Brazil, and Europe, by ensembles including the Nouvel Ensemble Moderne, the Esprit Orchestra, the Windsor Symphony Orchestra, the Bozzini Quartet, the Allsar Quartet, In Extensio, Toca Loca, Quasar, Sixtrum, Talea Ensemble, and the Ensemble Orchestral Contemporain de Lyon, as well as by the percussionist Fernando Rocha. He has been honored seven times by the SOCAN Competition for Young Composers, was a finalist for the Prix Jules Léger for new chamber music, and was awarded the Opus Prize for best premiere of the year 2007 for his duet for piano and percussion, Trans/Fusion. He was nominated again for the same competition in 2009. In 2006, he was selected to participate in the NEM Young Composers Forum in Amsterdam, and more recently in the CBC Evolution competition. He has participated in several courses with institutions such as Domaine Forget, Royaumont, the National Arts Centre, and IRCAM, in parallel with his studies at McGill University. He also performs with Veronica Charnley and the Montreal-based indy rock band Flotilla. He is currently pursuing a doctorate at Columbia University in New York City.