A week before filming began, director Kevin Greutert was informed that the film would be post-converted to 3D. He was upset at this decision as he hadn't planned or storyboarded such a move. The idea was dropped for this installment due to time constraints but resurrected for the next film in the film series, Saw 3D (2010).
Director Kevin Greutert mentioned in the commentary track that the twitching and shivering Amanda (Shawnee Smith) does in her scenes with Cecil (Billy Otis) was real due to low temperatures and rain in Toronto at the time of filming. Shawnee couldn't stop shivering because she was cold and they were shooting outdoors.
VH1's reality show Scream Queens (2008) winner Tanedra Howard won a role for this film. She plays Simone.
Is the first installment of the franchise where Billy the Puppet appears in person to deliver the rules of a game, rather than a warning or a congratulations message.
This is the lowest-grossing "Saw" film. All of the other installments earned over $100 million at the worldwide box office; this one only made $68 million. Saw 3D (2010) (originally titled "Saw 3D") was originally intended to be released in two parts, but the disappointing box office performance of this film led to "Saw 3D" being released as a single film.