Unlike the other Japanese horror remakes like The Ring (2002), Dark Water (2005), Pulse (2006), and One Missed Call (2008), this was the only film out of all the others that actually remained in Japan instead of moving the story to America.
Before filming, the cast and crew went through a ceremony where they were blessed so that nothing bad could happen to them for filming.
Jason Behr met KaDee Strickland on the set of the film and both began dating due to their interest in Japanese culture (which is why they accepted their roles in the film) despite not sharing any scenes together in the film. They eventually married two years later.
Yuya Ozeki, Takako Fuji, and Takashi Matsuyama all appeared in Ju-on: The Grudge (2002) and Ju-On: The Grudge 2 (2003), the Japanese films upon which this film was based, all reprising their roles as the doomed Saeki family.
The character of Toshio is almost always found with his cat. In real life, the boy who plays Toshio, Yuya Ozeki, was terrified of cats.