- Completely Different Title: Known in France under the similar but distinct title Conjuring 3 : Sous l'emprise du diable (Conjuring 3: Under the Devil's Influence).note A literal translation of the subtitle would be Le diable m'a obligé à le faire.
- Fake American: Ruairi O'Connor (Arne) is Irish, John Noble (Kastner) is Australian, and Ingrid Bisu (Jessica) is German-Romanian. The South African Shannon Kook also returns to play the Warrens' assistant Drew.
- Release Date Change: The film was supposed to be released on September 11, 2020, but the COVID-19 Pandemic delayed the release to June 4, 2021.
- You Look Familiar: Ingrid Bisu, who plays Jessica Strong, previously portrayed Sister Oana in The Nun.
Trivia / The Conjuring: The Devil Made Me Do It