- Friends Veronica Sawyer and Betty Finn are named after other fictional friends Veronica and Betty from the comic strip "Archie", and Tom Sawyer and Huckleberry Finn.
- Takes place in OHIO but filmed in CALIFORNIA.
- The high school is named "Westerberg High". Winona Ryder's favorite band at the time was "The Replacements", whose lead singer is named Paul Westerberg.
- Release date: March 31, 1989
- J.D. tricks Veronica into killing the jocks by claiming to use "ich luge" bullets, which he claims only pierce the skin. "Ich luge" is German for "I'm lying".
- Originally the book that suicidal students supposedly underline "meaningful" passages from was "The Catcher in the Rye. The producers could not get clearance to use this book and it was changed to "Moby Dick" instead.
- Grossed: $1,108,462 (USA)
- When Heather Duke gathers signatures for the Big Fun petition, one of the students stamps his name: Dennis Di Novi. This is a reference to the film's producer, Denise Di Novi.
- Filmed in 32 days.
- The original screenplay for Heathers had a different ending in which Veronica kills J.D. and puts the bomb to herself. The screen then fades to black ans you hear Veronica's voice say "boom". Then the final scene is in heaven and everyone is happy. New World thought this was too dark and made the producers change it.
- Veronica was originally writen with Jennifer Connelly in mind.
- Veronica's bedroom was built in the gym of the school they used in the film.
- Heather Duke's kitchen in the dream sequence was also the kitchen used for Heather Chandler's house. They just switched the colors and lit it differently.
- Kim Walker (Heather Chandler) and Lisanne Falk (Heather McNamara) also appeared together in "SAY ANYTHING"
- Had 3 working titles: "Lethal Attraction", "Westerburg High" & "Fatal Game"
- "HEATHERS" is Sarah Michelle Gellar's favorite movie. She knows every word.
- Directorial debut for Michael Lehmann.
- Daniel Walters screenplay won the 1989 Edgar Allen Poe Award for Best Screenplay.
- Filming began July 1988 in Studio City, California. Color by DeLuxe. Budget estimate $5 million.
- Nine minutes were cut from versions released to theaters in Utah.
- First shown in Milan, Italy at MIFED October, 1988. Also shown at the 1989 United States, Houston International, Seattle International, and Deauville Film Festivals.
- Released on video July 6, 1989.
- Rated BBFC 18 by the British Board of Film Classification.
- Brad Pitt read for the role of J.D. but producers thought he was too nice.
- Heather Graham got the role of Heather McNamara, but he parents made her drop out. The role later went to Lisanne Falk.
- Winona Ryder was didn't like the outfit she wore during the "Heather duke confrontation" so Producers Denise Di Novie ran out and found her a new one.
- Winona Ryder was 15 during shooting.
- Winona Ryder was the first person to be cast
- Tori Spelling showed "HEATHERS" to her dad, Aaron Spelling, who was casting "BEVERLY HILLS 90210". He liked what he saw with Shanen Doherty and asked her to read for the part of Brenda Walsh. She later got the role.
- Winona Ryder's agent begged her not to do the movie and siad it would be the end of her career.
- Lisanne Falk wore a wig during the first scene, which was shot a few months after the film finished.
- The "Strip Croquet" scene was filmed the night Winona Ryder had to attend the "BETTLEJUICE" premiere.
- Winona Ryder says that even if she wasn't in "HEATHERS" it would still be her favorite movie.
- Producer Denise Di Novi wrote a check to New World Pictures for an ad in the L.A. times because they couldn't affored to put on in there.
- The "Frat Party" scene was shot at an actual Frat House in UCLA.
- The line "You stupid fuck!" was actually writen as "You stupid cunt!".
- The final scene was actually shot in a boiler room underneath a school.
- The actor who plays the principal in the movie is actually a teacher at Beverly Hills High School.
