Following the album's release, "Kill Them With Kindness" was released as a single alongside its music video on 3 December 2020. Reception Ultra Mono received generally positive reviews upon release, with Metacritic awarding the album an aggregated score of 76 out of 100 based on 22 reviews, 19 of which were positive. Louder Than Wars John Robb declared Ultra Mono to be "the album of [Idles'] career" in a 10 out of 10 review, praising the album's themes, Launay's production and the band's performances throughout, concluding that "it's a wonderful record. It makes you dance, think, feel wild and gentle, sing and shout and want to change the world whilst embracing everyone you can in a physically socially distanced but mentally very socially attached kind of way." Jordan Bassett of NME was similarly impressed with the album, describing it as "a breakneck ride that roars through sarcasm, defiance, compassion and controversy." Qs Dorian Lynskey wrote that the album was "the sound of a band becoming ever more defiantly themselves", finding it "more adamantly political" and complimenting its "bludgeoning drums, scowling bass... great, slab like riffs" and the "hysterical urgency" permeating the track listing. Despite finding some of the lyrics to be crude and condescending, Lysnkey eventually stated that the record's "strengths are inseparable from its flaws", concluding that "IDLES' brute-force catharsis neither requires nor rewards subtlety... they are they. Take them or leave them." Tom Hull said that while the early comparisons of Idles to The Clash were "ridiculous" as the former lacks "both the early punk fury and the later pop knack", the band nonetheless achieves "a middle line, which supports today's fire and fury." Writing for AllMusic, Liam Martin was more reserved when appraising the album. Comparing it unfavourably to the band's previous albums, Martin stated that "there is much to enjoy here; their raucous energy shines just as bright, but underneath the surface Ultra Mono lacks the sparkle that made their first two records truly special." Conversely, JR Moores was much less favourable in his review for The Quietus, criticising the lyrics and a perceived misuse of the guest musicians featured on the record, classifying it as a "by-numbers rock plod", before rounding out his review with "three albums in and the hype has died down. The ideas are drying up. The lack of substance is wholly exposed." Jazz Monroe also criticised the album in a review