Bruce Willis tried to contact Matthew Perry to get him to take part in the film while, unbeknownst to him, Perry was on vacation. After a few weeks of trying to get hold of him, Willis left the famous line, "I will chop off your legs, set fire to your house, and watch you drag..." on Perry's answer machine. They thought it was so funny that they included it on the film.

The three kids who run between Jimmy and Oz when they are standing next to the flower cart are Bruce Willis's three daughters, Tallulah Willis, Scout Willis, and Rumer Willis.

The shot of Jill (Amanda Peet) twisting her ankle was not scripted. Director Jonathan Lynn liked the take, so it was put into the film.

Bruce Willis agreeing to guest appear on Friends (1994) for free, and because he lost a bet to Matthew Perry during filming, is actually an urban legend. In "People" Magazine, Star Spotlight 2000, 'Willis agreed to a guest stint on 'Friends' simply because he and Perry thought it would be fun.' News outlets mistakenly reported on the rumor and fans have been perpetuating it ever since. Willis was in fact paid for the role, including syndication runs, but donated the money to: The American Foundation for AIDS Research, AIDS Project Los Angeles, the Elizabeth Glaser Pediatric AIDS Foundation, the Rape Treatment Center, and UCLA Unicamp for underprivileged children.

The owners of the two houses that were used for this movie were paid $50,000 on the condition that they left their houses for a month.

The house used for filming was infested with flies, so it was nearly impossible to prevent them from appearing in several scenes.

The blues song that plays as Oz arrives in Chicago and meets his friend at the Oyster Bar is performed by Bruce Willis and his band. The harmonica solo featured in the song is played by Willis himself.

The whole nine yards phrase is from the 13th century, it is a bolt of fabric or 9 yards..when a monk would be walking up to purchase a monks habit, the tailor would say "Here comes the whole nine yards." As , it took 9 yards of fabric to create the monks habit, hence the term, the whole nine yards. That's one explanation. Others include the use of cloth for saris, kilts, and burial shrouds. Another uses it in the sense of cubic yards of concrete, and another from the length of a machine gun belt from a British Vickers machine gun. But no use has been traced to any time before about 1850.

When Volkswagen was approached about a product placement in the movie for its new Beetle, they said they would only pay if a male character drove the car, because there are already plenty of women who want to drive the new VW Beetles. However, it was decided that it was such a perfect car for Sophie (Rosanna Arquette) to drive that they would use it anyway, even though Volkswagen didn't pay them.

When Oz recognizes that his neighbor is Jimmy "The Tulip", the newspaper's picture that says "His Two-Lips" are sealed is actually from Die Hard 2 (1990).

Is the first mainstream American movie to be filmed on location in Montréal, Quebec.

At the time of the movie's release, many critics panned Rosanna Arquette's performance, claiming that she delivered her lines like a female Inspector Clouseau (Peter Sellers' character from The Pink Panther (1963) franchise). In his DVD commentary, director Jonathan Lynn stated that she worked with a dialogue coach and he was quite pleased with her accent.

When Matthew Perry is cutting the grass at the beginning of the movie, he's wearing a shirt with the crest of the hockey team, the Ottawa Senators. Matthew Perry spent some time growing up in Ottawa, Ontario.

When Oz recognizes that his neighbor is Jimmy "The Tulip", the newspaper's picture that says "Conversation With a Contract Killer" is actually from The Jackal (1997) in which Bruce Willis plays the titular contract killer.

The Biddles Jazz & Ribs club was named after legendary Montréal bassist Charles Reed Biddle. He appears in the nightclub scenes with his daughter, Stephanie, on vocals. Biddle passed away in 2003, and the club is now named House of Jazz.

At the start of the hit scene, an insert shot shows correct lock picking technique. Two tools are required: the pick for setting the locking pins to their unlocked shear line, and the torque wrench to hold the picked pins in place while turning the cylinder.

The original script called for the movie to take place in Florida instead of Quebec.

In Oz's hotel room, Cynthia (Natasha Henstridge) mentions thirty pieces of silver. This refers to the price for which Judas Iscariot betrayed Jesus Christ.

Bollywood made an unofficial remake of this film called Awara Paagal Deewana (2002).

Matthew Perry plays the main love interest opposite to Courteney Cox on Friends (1994). At the time of the film's release, Cox was married to David Arquette, the real life brother of Rosanna Arquette, who also plays Perry's character's wife here.

Rosanna Arquette and Bruce Willis previously appeared in Pulp Fiction, although they didn't share a scene.

Bruce Willis and Michael Clarke Duncan had previously co-starred in Armageddon (1998)

Kathy Griffin auditioned for the role of Jill, which eventually went to Amanda Peet.

Matthew Perry and Amanda Peet would go on to work together on Studio Sixty on the Sunset Strip.

The plane Janni Gogolak lands in is a 1973 GRUMMAN G-1159 Fixed wing multi engine, #N400M.

When the gang first comes to Kill Jimmy 'Bruce Willis' he is watching the movie "Key Largo" (1948) starring; 'Humphrey Bogart', 'Lauren Bacall', 'Edward G. Robinson', and 'Lionel Barrymore'.

Bruce Willis and Kevin Pollak also co-starred in The Whole Ten Yards (2004), Hostage (2005), and Cop Out (2010).

When Oz runs back to Jimmy's house as Jimmy and Jill are sitting at the table cleaning and loading guns, Jimmy is wearing a sleeveless white undershirt, belt and dress pants identical to Bruce's wardrobe in 'Die Hard'.

Amanda Peet acted alongside another NBC sitcom star earlier in her career. She played Jerry Seinfeld's girlfriend Lynette in the episode "The Summer of George."