Demonte Colony 3 has cleared censorship with an 'A' certificate — a first for the franchise, which had received U/A certificates for both its previous instalments. Director Ajay Gnanamuthu announced the development alongside a slight change in release date, moving it from September 11 to September 10. "The darkness is back. Not for the faint hearted. Brace yourself," he wrote.

Arulnithi and Priya Bhavani Shankar reprise their roles in the third chapter, with Guru Somasundaram playing a dreaded librarian who serves as the harbinger of death. The tagline reads "The End is Too Far." Sam CS returns to compose the music, with Sivakumar Vijayan handling cinematography. Sudhan Sundaram's Passion Studios backs the film alongside Dangal Media and RDX TV.