Unwelcome was generally well received by both critics and fans, being hailed as a return-to-form to their earlier materials compared to their 2010 release Starve for the Devil by focusing on aggression and technicality, but still remaining melodic and listenable.

Andrew Uscategui of Sputnik Music writes: "Also as you'd expect from Arsis, there's a decent amount of cheese on Unwelcome, if you didn't already get that notion from the ridiculous song titles.

'Sunglasses at Night' isn't necessarily their fault as it's a Corey Hart cover (which is odd enough as it is), but the lyrics are so blatantly awful it's almost impossible to ignore.

"[1] Despite this, he did give the album 3.5 out of 5 stars, saying that "Arsis deserves some credit for staying true to their technical melodeath roots after all this time.

Even after compromising their sound in the past, Unwelcome shows the band doing what they do best and doesn't completely rule out the idea of another A Celebration of Guilt or A Diamond for Disease sometime in the future."