Number 1 Angel is the third mixtape by English singer Charli XCX, released on 10 March 2017 by Asylum Records. The mixtape contains ten tracks and was created in Los Angeles as a collaboration with producer A. G. Cook, the founder of PC Music. Several other producers associated with the label also contributed to the mixtape, including Sophie who previously produced Charli XCX's extended play Vroom Vroom. Musically, it has been labeled as avant-pop and electropop.

Number 1 Angel received generally positive reviews from critics. Some reviewers praised its genre-bending sounds and guest appearances, while others found it repetitive.