After watching the film, Soojit Sarkar said "Few people didn't see my film October 2018 as it was very slow but please go and see 'Mulk'."
After meeting Manoj Pahwa and Rajat Kapoor on the sets, Anubhav Sinha decided to switch their roles.
Tapsee Pannu said that she prepared for the role of a lawyer by taking inspiration from her co-star Amitabh Bachchan from 'Pink' (2016).
Pratiek Babbar, who was to play a Muslim terrorist, was asked to watch the documentary 'Among the Believers' and read extensively about David Headley, an American terrorist of Pakistani origin.
Asutosh Rana and Tapsee Pannu were provided guidance for their characters during courtroom scenes by high-court retired Judge Nadeem Siddiqui from Lucknow.