Candy was born in 1950 in Newmarket, Ontario. The son of Sidney James Candy and Evangeline (Aker) Candy, he was brought up in a working-class Roman Catholic family. Candy's father was of English and Scottish descent, while his mother was of Polish and Ukrainian descent.
Candy studied at Neil McNeil Catholic High School, later enrolled in the Centennial Community College to study journalism, and went to McMaster University for higher education. His first film role was a small, uncredited appearance in the 1973 film Class of '44. He appeared in several other low-budget films during the 1970s, including the bank-robbery thriller The Silent Partner with Christopher Plummer and Elliott Gould. In 1975, he played Richie, an accused killer, in episode "Web of Guilt", on the Canadian TV show Police Surgeon. In 1976, Candy played a supporting role (with Rick Moranis) on Peter Gzowski's short-lived, late-night television talk show, 90 Minutes Live. That same year, as a member of Toronto's branch of the Second City, he gained wide North American popularity, which grew when he became a cast member on the influential Toronto-based comedy-variety show Second City Television (SCTV). NBC picked the show up in 1981 and it quickly became a fan favourite. It had won Emmy Awards for the show's writing in 1981 and 1982.
Among Candy's memorable characterizations for SCTV were unscrupulous street-beat TV personality Johnny LaRue, 3-D horror auteur Doctor Tongue, sycophantic and easily amused talk-show sidekick William B. Williams, and Melonville's corrupt Mayor Tommy Shanks. Other characters included the cheerful Leutonian clarinetist Yosh Shmenge, who was half of the Happy Wanderers and the subject of the mockumentary The Last Polka, folksy fishin' musician Gil Fisher, handsome if accent-challenged TV actor Steve Roman, Pippy Long Socks, hapless children's entertainer Mr. Messenger, corrupt soap-opera doctor William Wainwright, smut merchant Harry, "the Guy With the Snake on His Face", and Giorgy, everyone's favourite Cossack.
Mimicry was one of Candy's talents, which he used often at SCTV. Celebrities impersonated by Candy include Jerry Mathers, Divine, Orson Welles, Julia Child, Richard Burton, Silvio Gigante, Luciano Pavarotti, Jimmy the Greek, Andrew Sarris, Tip O'Neill, Don Rickles, Curly Howard, Merlin Olsen, Jackie Gleason, Tom Selleck, Gordon Pinsent, Darryl Sittler, Ed Asner, Gertrude Stein, Morgy Kneele, Doug McGrath, and Hervé Villechaize.
In 1979, Candy took a short hiatus from SCTV and began a more active film career, appearing in a minor role as a US Army soldier in Steven Spielberg's big-budget comedy 1941 and had a supporting role as corrections officer Burton Mercer in The Blues Brothers. A year later, Candy played the lovable, mild-mannered Army recruit Dewey Oxberger in 1981's Stripes, one of the most successful films of the year. In 1983, Candy had a small but memorable cameo appearance in Harold Ramis's National Lampoon's Vacation and appeared on Saturday Night Live twice (hosting in 1983) while still appearing on SCTV. According to writer-comedian Bob Odenkirk, Candy was reputedly the "most-burned potential host" of SNL, in that he was asked to host many times, only to be told 'no thanks' by the SNL staff at the last minute.
In 1983, Candy headlined in the film Going Berserk, and was also approached to play the character of accountant Louis Tully in Ghostbusters (completed and released in 1984), but ultimately did not get the role because of his conflicting ideas of how to play the character; the part went instead to Rick Moranis. Candy was one of the many celebrities who appeared chanting "Ghostbusters" in Ray Parker, Jr.'s hit "single" for the movie. In 1984, Candy played Tom Hanks's womanizing brother in the hit romantic comedy Splash, generally considered his break-out role.
Throughout the latter half of the 1980s, Candy often took roles in substandard films (even performing the voice of a talking horse in the Bobcat Goldthwait comedy Hot to Trot). While continuing to play supporting roles in films such as Spaceballs, Candy headlined or co-starred in such comedy movies as Volunteers, Planes, Trains and Automobiles, Brewster's Millions, The Great Outdoors, Armed and Dangerous, Who's Harry Crumb?, Summer Rental, and Uncle Buck. He also continued to provide memorable bit roles, including a disc jockey in the comic musical film Little Shop of Horrors and a policeman in the Sesame Street film Follow That Bird.
Candy also produced and starred in a Saturday-morning animated series on NBC titled Camp Candy in 1989. The show was set in a fictional summer camp run by Candy, featured his two children in supporting roles, and also spawned a brief comic book series published by Marvel Comics' Star Comics imprint.
In the early 1990s, Candy's career went into decline after he appeared in a string of critical and commercial failures, including Nothing but Trouble (for which he was nominated for a Razzie as "worst supporting actress", playing a woman), Delirious, and Once Upon a Crime, although he did appear in major successes such as Rookie of the Year (uncredited), The Rescuers Down Under, Home Alone, and Cool Runnings.
Candy attempted to reinvigorate his acting career by broadening his range and playing more dramatic roles. In 1991, Candy appeared in a light romantic drama, Only the Lonely, which had him as a Chicago cop torn between his overbearing mother (Maureen O'Hara) and his new girlfriend (Ally Sheedy). The same year and in rare form, Candy played a dramatic role as Dean Andrews Jr., a shady Southern lawyer in Oliver Stone's JFK. He made his directorial debut in the 1994 comedy Hostage for a Day, in which he also made a cameo appearance.
In 1991, Bruce McNall, Wayne Gretzky, and Candy became owners of the Canadian Football League's Toronto Argonauts. The celebrity ownership group attracted attention in Canada and the team spent a significant amount of money, even signing some highly touted National Football League prospects such as wide receiver Raghib Ismail. The Argonauts took home the 1991 Grey Cup, beating Calgary, 36–21, in the final.
In 1994, while on vacation from film production (Wagons East!) in Mexico City, Mexico, Candy called his friends, including Canadian Football League commissioner Larry Smith, and told them that he had just let go of his team and was putting it up for sale. He then called his assistant, who invited Candy to play golf with him in the spring when he returned to Toronto. After cooking a late lasagna dinner for his assistants, Candy called his co-stars from his hotel, then went to sleep. Some time after midnight, on March 4, 1994, Candy was found dead from a presumed myocardial infarction even though this was unproven as no autopsy was performed. He was 43. The heavyset Candy had struggled for some years with weight-related health issues.
Candy was survived by his wife, Rosemary Hobor, and his two children, Jennifer and Christopher Candy.
Candy was in talks to portray Ignatius J. Reilly in a now-shelved film adaptation of John Kennedy Toole's Pulitzer Prize-winning novel A Confederacy of Dunces. He even expressed interest in portraying Atuk in a film adaptation of Mordecai Richler's The Incomparable Atuk and Roscoe "Fatty" Arbuckle in a biopic based on the silent film comedian's life. These three shelved projects have been referred to as "cursed" because Candy, John Belushi, Sam Kinison and Chris Farley were each attached to all three roles, and they all died at early ages before they could make any of these films.
Candy was also slated to collaborate with John Hughes in a comedy film opposite Sylvester Stallone titled Bartholomew vs. Neff. This project, also shelved, was about two feuding neighbours who were to have been portrayed by Candy and Stallone.
Candy was originally considered to play Alec Guinness's role in the remake of the 1950 film, Last Holiday, with Carl Reiner directing. A little over a decade after his death, the role was played by Queen Latifah.
Candy also had the comic relief role of the turkey Red Feather in the animated Disney film Pocahontas written for him. The role was subsequently cut from the film after his death.
Candy's funeral was held at St. Martin of Tours Catholic Church. Candy was entombed in the mausoleum at Holy Cross Cemetery in Culver City, California. His crypt lies just above fellow actor Fred MacMurray. On March 18, 1994, a special memorial service for Candy, produced by his former improvization troupe, the Second City, was broadcast across Canada.
Wagons East! was completed using a stunt double and special effects and released five months after Candy's death. His final completed film was Canadian Bacon, a satirical comedy by Michael Moore that was released a year after Candy's death. Candy played American sheriff Bud Boomer, who led an "invasion" of Canada. Candy recorded a voice for the TV film The Magic 7 in the early 1990s. The film remained in production for years due to animation difficulties and production delays, and it was shelved. Candy was inducted into Canada's Walk of Fame. In May 2006, Candy became one of the first four entertainers ever honoured by Canada Post by being featured on a postage stamp. Blues Brothers 2000 is dedicated to three people, including Candy, who played a supporting role in the original Blues Brothers. A tribute to Candy was hosted by Dan Aykroyd at the 2007 Grey Cup festivities in Toronto in November 2007.
Ween's Chocolate and Cheese album, released in 1994, is "dedicated in loving memory to John Candy (1950–1994)". At the time Gene Ween remarked, "there was so much going on about Kurt Cobain, and nobody mentioned John Candy at all. I have a special little spot in my heart for him."
The John Candy Visual Arts Studio at Neil McNeil Catholic High School, in Toronto, Ontario, was dedicated in his honour after his death. Candy, one of the school's most famous alumni, said during one of his annual visits to the school, "My success is simply rooted in the values and discipline and respect for others that I was taught at Neil McNeil." Candy's daughter, Jennifer Candy, is an actress and television producer, having production credits for the television series Prom Queen and Sam Has 7 Friends.
Support is growing for giving the Canadian Screen Awards the official nickname "The Candys," both in honour of the actor and how the name suggests Canada, as well.