[1][2] The soundtrack album featured original compositions from Alexandre Desplat and supplemented existing music by Benjamin Britten, as well as classical songs from Hank Williams, Leonard Bernstein, Frank Schubert and Françoise Hardy.

He supplemented those tracks, with the help of music supervisor Randall Poster, in their seventh collaboration; they worked together since Anderson's feature directorial debut Bottle Rocket (1996).

That's been the predominant mode for some time [...] Britten conducted and produced and directed the first production of Noye's Fludde, but after that, it becomes something where a group of people in Texas can get all these pieces of sheet music, and this instruction manual, and do their own take on it.

[19] Alarm's Meaghann Korbel wrote "the soundtrack is really couldn’t be more perfect for the story: children are teaching adults about matters beyond their own comprehension, whether it’s life’s complexities or the intricacies of developing a classical composition with a full-on orchestra — as though it’s just that easy.

[21] Heather Phares of AllMusic wrote "While Moonrise Kingdom's choices set it apart from other Anderson films, its effortless flow, appropriateness, and vivid beauty make it another fine musical companion to his work.

"[24] The Hollywood Reporter's Todd McCarthy wrote "Music by Britten is dominant, particularly from Noye’s Fludde (Noah’s Flood), a work by the English composer first performed in 1958 that could have been appropriated by Anderson for use in this watery context or, more likely, served as inspiration for the inundation that climaxes the film.

The Guardian's Peter Bradshaw had stated "the music is an interesting assertion of the uncool, stolidly Anglo-Saxon character of this parochial, islanded corner of America – evoked not with conventional nostalgia, rather with a connoisseurship of how strange and different it seems.

"[31] In an article to The New Yorker magazine, classical musician and music teacher, Russell Platt had stated the use of Noye's Fludde as "so transformative is its place at the core of the story, and not just in the mere outlines of its plot".

The measured precision of the music matches Anderson’s extensively mapped-out camera movements and mise-en-scene [...] The film’s end credits include Moonrise Kingdom’s composer Alexandre Desplat’s tribute to the Young Person’s Guide, with a narrator introducing each separate instrument as it makes its entrance.

[32]Considering the use of Britten's opera aria, A Midsummer Night's Dream, Lin said "the selection is a choral lullaby sung by the fairies to the four mortal lovers who have fallen asleep in the forest.

The shifting chromatic harmonies of the piece (not to mention the coolly detached tone of the kids’ letters) helps prevent the innate pathos of Sam and Suzy’s childhood from becoming too pronounced.