III received generally positive reviews from music critics. At
Metacritic, which assigns a
weighted mean rating out of 100 to reviews from mainstream critics, the album received an average score of 76, based on 33 reviews, which indicates "generally favorable reviews". Louis Pattison of
NME commented that, "in toning down the shock and awe, [Crystal Castles have] revealed the beating heart at the centre of their work. The message, still, is that the world is a cruel and fucked-up place. But being doomed seldom sounded so beautiful."
AllMusic's Heather Phares viewed
III as the duo's "most serious set of songs yet" and stated, "Artistic progress is as much about subtraction as it is about addition, and on
III, Crystal Castles have made room to be sad, angry, pretty, and danceable at the same time."
Pitchforks Ian Cohen dubbed
III "the duo's most focused record", adding, "While not as immediately striking as either
Crystal Castles (I or
II), the streamlined sound allows more maneuverability and subtle variety in the actual songwriting." Matt James of
PopMatters wrote, "Perennial outsiders to the death, Crystal Castles' third act is inspiring, warped, feverishly uncomfortable, bold, bloody and brilliant." Dan Pfleegor of
Consequence of Sound opined that "
III is less playful than the duo's previous couple of offerings, but its thematic mood is much tighter and more fully realized."
The Guardians Tim Jonze noted that "
witch house is an obvious influence [on the album], and you could question whether the former
chip-tune terrorists are still as ahead of the curve as they once were. It hardly matters when they can come up with stuff like 'Child I Will Hurt You', a dream-state lullaby that is both beautiful and unbearably sorrowful."
Simon Price of
The Independent stated that the album "shudders and shimmers like some massive, monstrous machine. But, when heard loud, the more accurate metaphors come from nature: flashes of lightning at the top end, earthquakes and landslides at the bottom." In a mixed review, Jesse Cataldo of
Slant Magazine described
III as "earnest, expansive
electronica from a duo few are expecting such sincerity from, and it edges them directly into the middle of the road", concluding, "In striving for something new, the duo has only found a more recognizable sort of tedium."
Annie Zaleski of
The A.V. Club expressed that, "instead of anarchist dance jams full of crunchy
8-bit noise,
(III) is more like a static-filled radio station fading in and out of range." Zaleski continued, "While
(III) can use this disorientation effectively [...] too often the music is irritating, not disruptive." Hermione Hoby of
The Observer felt that "there's very little on this third LP that could qualify as '
experimental'. Track after track leans heavily on the relentless
four-to-the-floor of
trance, with Alice Glass's yelped vocals muffled under a weight of sound that's simultaneously boring and abrasive." In 2023, the song Kerosene
went viral on
TikTok and is used in
aviation edits.
Accolades ==Commercial performance==