[7] In an interview with Malayala Manorama, Devadath V. S., a Kuruppanthara native and Kalaripayattu trainee who played the character Basil, told that he was chosen by the assistant director, Krishnamani.

[16] Baradwaj Rangan of Galatta Plus gave 4 out of 5 stars and wrote "We have seen Dileesh Pothan in a number of films now, but Baby is possibly his best role, and he delivers a brilliantly minimalist performance.

"[17] Vignesh Madhu of The New Indian Express gave 3.5 out of 5 stars and wrote "Although the film doesn't boast of anything groundbreaking in terms of its writing, its such competent execution, with the right mix of thrills, that makes it an engaging watch... on the big screen.

"[18] S. R. Praveen of The Hindu wrote "O.Baby explores feudal society through the minds of a few young people, who want to break free from the stifling atmosphere.

"[19] Swathi P. Ajith of Onmanorama wrote "O.Baby stands as a commendable endeavour by Ranjan Pramod to bring forth a profoundly serious theme to the public.

"[20] Sanjith Sidhardhan of OTTPlay gave 3.5 out of 5 stars and wrote "Director Ranjan Pramod's O.Baby is a thoroughly engaging drama-thriller that asks pertinent questions about social oppression and also help bridge that generation gap a bit.

"[21] Arjun Ramachandran of The South First gave 3 out of 5 stars and wrote "O.Baby is an intense dark thriller that discusses pertinent issues revolving around the backward class and the privileged ones.