Reitman was born in Komárno, Czechoslovakia (now in Slovakia), the son of Klara and Ladislav "Leslie" Reitman. Reitman's parents were Jewish; his mother survived the Auschwitz concentration camp and his father was an underground resistance fighter. His family came to Canada as refugees in 1950. Reitman attended Oakwood Collegiate in Toronto and was a member of the Twintone Four singing group.
Reitman attended McMaster University, receiving a Bachelor of Music in 1969. At McMaster he produced and directed many short films.
Reitman's first producing job was with the then-new station CITY-TV in Toronto. CITY was also the home of the first announcing job of his later friend and collaborator Dan Aykroyd. However, Reitman's tenure at CITY was short and he was fired during his first year by station owner Moses Znaimer.
In Toronto, he produced the stage production Spellbound (1973) which evolved into Broadway production The Magic Show.
Reitman's first commercial film ventures were as producer of two films for director David Cronenberg, Shivers (1975) and Rabid (1976). His big break came when he produced National Lampoon's Animal House in 1978 and directed Meatballs in 1979. From there, he directed and produced a number of comedies including Stripes (1981), Ghostbusters (1984), Legal Eagles (1986), Twins (1988), Ghostbusters II (1989), Kindergarten Cop (1990), Dave (1993), Junior (1994), Six Days, Seven Nights (1998), Evolution (2001), My Super Ex-Girlfriend (2006), and No Strings Attached (2011).
In the early 1990s, Reitman began to direct fewer films, but increased his role as a producer and executive producer through his company, Northern Lights Entertainment. He helped to produce the animated film Heavy Metal (1981), as well as the live-action films Spacehunter: Adventures in the Forbidden Zone (1983), Beethoven (1992), Beethoven's 2nd (1993), Space Jam (1996), Howard Stern's film Private Parts (1997), Road Trip (2000), Old School (2003), EuroTrip (2004) and Trailer Park Boys: The Movie (2006).
Reitman is a founder of the McMaster Film Board at McMaster University in Hamilton, Ontario. In 2007, Reitman was inducted into Canada's Walk of Fame. Reitman founded The Montecito Picture Company, a film production company located just south of Santa Barbara, founded in 2000.
He next produced the comedy I Love You, Man (2009), starring Paul Rudd and Jason Segel. Also in 2009, he produced the Academy Award-nominated film, Up in the Air, directed by his son Jason Reitman. Later, Reitman had planned to direct the erotic thriller Chloe (2009), but he couldn't attract the cast he wanted; so Reitman decided to only serve as a producer and asked Atom Egoyan to direct the film. Chloe has since enjoyed commercial success and became Egoyan's biggest moneymaker ever.
Reitman co-produced the biographical film Hitchcock, released on November 23, 2012. Reitman also directed the 2014 sports drama Draft Day, starring Kevin Costner.
In the early 1980s, Tom Mankiewicz wrote a script for a film entitled The Batman, with Reitman attached to direct. He planned to cast Meatballs star Bill Murray as Batman, David Niven as Alfred Pennyworth, William Holden as Commissioner James Gordon, and singer David Bowie as The Joker. However, due to Holden's and Niven's death and the rewrites of the script, Reitman left the project and Gremlins director Joe Dante entered in the project, but the film never materialized.
In April 1996, it was reported that Reitman was attached to produce, and possibly direct, a Wonder Woman film. However, three years later, he passed the project on to writer Jon Cohen and left for unknown reasons.
In March 2007, New York magazine, citing no sources, stated that Sony Pictures Entertainment wanted to replace Reitman on Ghostbusters III with a younger director, but that Reitman's original contract precluded this. In early 2010, it appeared as if Reitman would direct the film, but in September 2014, time later after Harold Ramis' death, Paul Feig was officially set to direct a new film, which was released in 2016 as a reboot of the franchise.
In March 2012, it was reported that a sequel of Twins, entitled Triplets, was in the works, and that Reitman will co-produce the film. A release date wasn't given since the announcement.
In 2013, it was revealed that Reitman had plans to make a sequel to Evolution, but plans for a sequel never materialized.
In May 2016, Reitman revealed that he was in talks with Warner Bros. chairman Bob Daly about his possible involvement in Space Jam 2, the sequel of Space Jam. A month later, it was reported that Reitman will produce the upcoming animated series Ghostbusters: Ecto Force.
Reitman has been married to Geneviève Robert since 1976. Reitman has a son and two daughters. His son, Jason Reitman, is a film director best known for his films Juno, Thank You for Smoking and Up in the Air, for which he won a Golden Globe for his screenplay. His daughter Catherine Reitman is a member of The Groundlings comedy troupe in Los Angeles. His other daughter, Caroline Reitman, is a sophomore at Santa Barbara City College. Reitman's wife is a convert to Judaism.
In 2009, he was made an Officer of the Order of Canada "for his contributions as a director and producer, and for his promotion of the Canadian film and television industries".
In April 2011 he received the Mayor's Prize at his native city of Komárno, Slovakia.
1 Schwarzenegger's appearance is a cameo as himself when he was chairman of the President's Council on Physical Fitness and Sports.