In July 2019, Dan Romer was announced as composer for the film's score, having previously worked with Cary Joji Fukunaga on Beasts of No Nation and Maniac.

[5] It is the first time in the Bond series history that a composer has been replaced during post-production, and the second major personnel change for the film after Danny Boyle left as director.

[7][8] In January 2020, Billie Eilish was announced as the performer of the film's theme song, with her brother, Finneas O'Connell, serving as co-writer as well as the track's producer.

Step forward, Billie Eilish, the world’s most melancholic teenage pop star, who wraps her intimate, whispered vocals over words that, in proper Bond style, seem on the surface to be profound but in fact don’t mean much at all.

While the dramatic power ballad, with her trademark whispery vocals and sweeping strings, was acclaimed and won a Grammy Award in March, the recording process wasn’t so smooth.