The album encompasses many genres, and its title refers to the band's goal of making each song its own "isle" with a distinct musical style.

[2] The album has a relaxed feeling, with rhythmic yet varied beats and a unique blend of reggae, pop, and electronica.

[4] Greg Kot of The Chicago Tribune called the album "deceptively breezy", while praising Natalie Bergman's vocals and questioning Elliot's.

She described the album as "exotic" while also highlighting songs such as "Twisted", in which she contrasted Natalie's vocals to "a greyscale Lily Allen".

[7] MusicOMH was also negative with its review of Isles, rating it only two and a half stars while describing the album's material as "mundane" and "turgid".