Production
The rights to Koontz' book were initially purchased by producer Steven Lane, a producer on The Howling series. Producer Joel Soisson, after reading the book, spent the next ten years pursuing the rights and was instrumental in getting the film set up at Miramax Films. It would be handled by Miramax Films' horror-focused label Dimension Films, who produced it in conjunction with Japanese company Fuji Creative. Due to Fuji's involvement, the film's country of origin is sometimes listed as being both the United States and Japan.
Phantoms was filmed on location in Georgetown, Colorado in late 1996, with over five sets of reshoots later happening in 1997. The Hotel de Paris Museum was used to depict the bakery and hotel where several scenes were set. While the film was in post-production during the first half of 1997, actress Joanna Going flew to New Zealand for three months to shoot another Miramax film titled Heaven. Post-production on Phantoms was originally intended to wrap around mid-1997, and Dimension/Miramax announced a release date of October 24, 1997, in time for Halloween. However, it was delayed to January 1998. The film still has a 1998 copyright date in the credits, as there were further post-production changes done shortly before the film's release. Actor Ben Affleck had cosmetic work done on his teeth for the film Armageddon, which was shot in late 1997, and in reshoots for Phantoms, his teeth appear noticeably whiter than in scenes that were shot earlier.
In 2017, Rose McGowan claimed that she was sexually assaulted by Miramax boss Harvey Weinstein while attending the Sundance Film Festival in January 1997. She was at the festival promoting Going All the Way, a non-Miramax film which also starred both McGowan and Affleck. McGowan further claimed that shortly after the assault, she did a photoshoot for Phantoms, where she revealed to Affleck what had happened to her, with Affleck allegedly responding by saying that he'd already told Weinstein to stop engaging in this behaviour. Affleck did not publicly respond to this allegation McGowan made about him. In early 2018, Weinstein's lawyer Ben Brafman released an email which he claimed disproved this allegation, and the matter never made it to court.