Garrett List (September 10, 1943 – December 27, 2019) was an American trombonist, vocalist, and composer.

List was born in Phoenix, Arizona. In 1950, he moved with his family to southern California. At the age of 18, he was teaching, playing, and composing classical, jazz, and pop music. In 1965 he left California and settled in New York City, where he attended the Juilliard School of Music. He encountered the Italian composer Luciano Berio and the conductor Dennis Russell Davies, with whom he formed the Juilliard Ensemble. This ensemble permitted him to meet Henri Pousseur and Pierre Boulez.

In the 1970s, he developed an interest in free jazz and met John Cage, Frederic Rzewski, Steve Lacy, and LaMonte Young. He was a member of Italian band Musica Elettronica Viva. In 1981, Henri Pousseur invited him to establish the improvisation class at the Conservatoire Royal de Musique de Liège, where his students included Fabrizio Cassol, Michel Massot and Aston Keaton alias Acétone. He wrote pieces for Man Ray movies as well as for Fernand Léger, Hans Richter, and Paul Gonze.

List died in Liege, Belgium, aged 76.