[19] Writing in the Liverpool Echo, Jade Wright deemed the track "colossal and extremely addictive", and said that Ora "returned in style".

[23] The Irish Times named it their track of the week, with Ailbhe Malone writing, "This falls into one of our favourite musical subgenres – the emotional banger".

[24] Writing in Time, Nolan Feeney said the track was "synthtastic" and "gives the singer reasons to keep trying", concluding, "This doesn't feel like the mega-smash single that will completely reverse her luck, but its you-ooo-ooh-ooh hook shows she can be a worthy vessel of solid material".

[25] Conversely, Dana Rose Falcone of Entertainment Weekly said the single "falls in line" with Ora's "poppy hits", "I Will Never Let You Down" and "How We Do (Party)" (2012).

[14] While Lewis Corner and Amy Davidson of Digital Spy commented that it lacked the "instant pull" of "I Will Never Let You Down", but had "solid chart potential nonetheless".

[7] Andrew Hampp of Billboard gave "Poison" three out of five stars, and said that it did not "match the playful aesthetic" of "I Will Never Let You Down", but its "belted, from-the-gut chorus may prove to be stickier".

[26] Poison debuted at number three in the UK singles chart with first-week sales of 55,855 units marking Ora's eighth top 10 hit.

[42] Idolator's Christina Lee wrote that in a live setting, Ora's "powerful vocals [in the song] are more pronounced, to where she sounds like she's taking the subject matter to heart".

[5] Writing in the Daily Express, Becca Longmire said Ora "flashed a lot of flesh" with her "revealing" outfit which she felt "arguably overshadowed the music".