No school would this allow production to film on their campus. The campus featured in the movie was actually cobbled together from 8 different shooting locations, including an abandoned bank building, a private residential home, and constructed sets.
Outdoor scenes were incredibly cold, which made them unbearable to shoot. Inanna Sarkis (Alice) said she would get a sponsor to provide them with winter coats and showed up on set the very next day with expensive winter coats for the cast.
Writer/director Simon Barrett originally pictured Suki Waterhouse as Alice, but he changed his mind after Inanna Sarkis auditioned.
Marina Stephenson Kerr was offered a part because of her performance in Channel Zero (2016), as the film's director, Simon Barrett, is friends with E.L. Katz, who directed the final season of the SyFy series.
Djouliet Amara was offered to wear a shirt or a bra or a bandeau during the shower scene, but she assured the crew that "a little bit on the bottom" and the pasties would be enough for her.