Bill Murray improvised the "Cinderella story" sequence from two lines of stage direction. Director Harold Ramis simply asked Murray to emulate a kid announcing his own fantasy sports moment. Murray simply asked for four rows of 'mums and did the scene in one take.

Cindy Morgan (Lacy Underall) has said that the oil massage scene with Chevy Chase was also completely improvised. When Lacy exclaims "You're crazy!" that was Morgan genuine reaction to Chase dousing her with oil.

The noise the Gopher makes are actually vocalized by a dolphin, and the dolphin sound effects used are the same ones that were used for "Flipper" (1964).

The character of Lou, played by the film's co-writer Brian Doyle-Murray, is the only one to actually say the word "caddyshack".

According to Scott Colomby on the DVD extras, he only took up smoking after playing the part of cigarette-puffing Tony.

The movie was inspired by writer and co-star Brian Doyle-Murray's memories working as a caddy at a golf club. His brother Bill Murray and director Harold Ramis also worked as caddies when they were teenagers.

The reason the scenes of Mr. Gopher's underground world look better than the rest of the film is because they were film on a sound-stage with better quality film stock and cameras rather than on location like the majority of the film.

The song being played by the musical horn on Al Czervik's Rolls Royce is "We're In The Money".

The movie's line "Cinderella story. Outta nowhere. A former greenskeeper, now, about to become the Masters champion. It looks like a mirac...It's in the hole! It's in the hole! It's in the hole!" was voted as the #92 movie quote by the American Film Institute (out of 100).

Premiere voted this movie as one of "The 50 Greatest Comedies Of All Time" in 2006.

In the scene where the Bishop (played by veteran actor Henry Wilcoxon) is having his best round of golf ever during a thunderstorm, he misses an easy putt, looks skyward and yells "rat farts!", and is immediately struck down by a bolt of lightning. The background music in this scene was from Cecil B. DeMille's classic The Ten Commandments (1956), in which Wilcoxon played the part of Pentaur.

The movie's line "So I got that going for me, which is nice." was voted as the #49 of "The 100 Greatest Movie Lines" by Premiere in 2007.

The rowdy, improvisational atmosphere around the filming, created by Harold Ramis, Bill Murray, Chevy Chase, and Rodney Dangerfield, didn't sit well with all the members of the cast. Ted Knight, widely regarded as a very nice man, got fed up with the constant shenanigans. Initially, Murray's and Dangerfield's role were to be cameo appearances. But their deft improvising caused their roles to be expanded much to the chagrin of Scott Colomby and some of the other cast members whose roles were reduced as a result.

Unsurprisingly, the movie is a huge favorite among golfers and golf fans. Tiger Woods so adores the movie, he played Carl Spackler in an American Express commercial that included references to many of the movie's most famous scenes.

Harold Ramis based the character of Carl Spackler on a slightly deranged police officer who was a shell-shocked war veteran.

The gopher sequences were written and filmed after most of the movie was shot. Originally, director Harold Ramis wanted to cast a live animal to play the gopher. When that did not work out, the animatronic gopher and its tunnels were built by John Dykstra.

According to 'Harold Ramis (I)' on the DVD Commentary, he claims that he wanted to score the movie to Pink Floyd music but the studio wouldn't allow him to do that.

Ranked #7 on the American Film Institute's list of the 10 greatest films in the genre "Sports" in June 2008.

Continuity

When Maggie and Danny are in bed, Tony jumps up to look in the window. Each time he jumps he gets no higher than the bottom part of the window. When they show him standing outside, he is actually taller than the bottom part of the window.

The letters on Angie's "Night Rider" shirt are reversed when he is seen sneaking between trees during the big money game.

The first time Lacey Underall appears, she is walking towards a bunch of caddies and holding a tennis racket. Moments later, she gets to the group of people and holding a golf glove.

When Ty is demonstrating night-putting to Danny and hitting each ball in the hole, in one shot the ball visibly goes past the hole, but in the close up the ball goes in the hole.

The golf clubs that Ty spills vanish by the time that Danny takes his shot.



Factual errors

According to golf rule 16-2, When any part of the ball overhangs the lip of the hole, the player is allowed enough time to reach the hole without unreasonable delay and an additional ten seconds to determine whether the ball is at rest. If by then the ball has not fallen into the hole, it is deemed to be at rest. If the ball subsequently falls into the hole, the player is deemed to have holed out with his last stroke, and must add a penalty stroke to his score for the hole. Danny never reaches the hole due to the explosion and therefore rule 16-2 is not invoked. The match stands as is. Danny and Ty win.

The end credits do not feature a listing for Earth Wind & Fire's "Boogie Wonderland."

When Dr. Beeper grabs his pager while he is wet, he nearly gets electrocuted. That small device would never actually produce enough power to do that.

When Czervik throws money at the band, they start playing. The song you hear has instruments that are not present in the band. You can tell they are playing the recording.

At the beginning of the boating scene when Al takes over for his captain, he uses both hands to accelerate the two throttles of both engines of the twin-screw boat. At the end or the scene when he shuts down the engines, he only operates the lever for the port engine leaving the starboard one at full throttle. His boat would not have stopped.



Incorrectly regarded as goofs

While Danny making that last putt effectively tied the game, meaning neither team lost or won, Al's last-second bet of "Double or nothing he makes it" essentially negates the original bet and creates a new one. Since Judge Smails agrees to this new wager before Danny makes the putt, Smails loses the final bet and must pay up.

All of the characters named "Smails" (the Judge, his wife, Spaulding) are listed as "Smalls" in the closing credits. But it is stated many times in the film that their last name is "Smails". This is likely a typo in the end credits, however, it is entirely possible that their surnames are spelled "Smalls", however, they pronounce it "Smails".

When Ty doubles the amount of the bet in the bar scene, he doubles it to $40,000 and tells Judge Smalls that his dad never liked him. Later on, Al and Ty double the amount of the bet again, to $40,000 apiece (from the previous $40,000 per team).

When the Bishop is playing his miraculous round of golf, lightning is prominent in the sky. No club would allow players on the course during a lightning storm. Clearly the bishop is having an unauthorized round of golf during the storm, hence his use of Carl as a caddy instead of an actual caddy.

When Al "breaks" his arm in the final game, he says the game is a draw. Judge Smails responds by saying, "No you don't, Czernik!" but Al's last name is Czervik with a V. Judge Smails either doesn't not know Al's correct last name, or simply doesn't care because he does not respect him.



Revealing mistakes

The wake from the large boat is moving in reverse.

During the scene of the party at the club, Carl hunts the gopher with his gun outside. He is moving from tree to tree, and you can see in the background that it is the daytime when it's supposed to be night.

The lamp on the desk that the Judge pushes to the right doesn't have a cord.

When Lacey dives off the board during the pool scene, it's clearly a stunt double with bright blond hair. Lacey's hair is much darker and not as full as the double's.

When Carl is trying to grab the gopher in his hole, you can see the wall of the "tunnel" move.



Miscellaneous

Danny and Ty talk about Bushwood being in Nebraska. Judge Smail's Rolls Royce has Illinois tags on it.



Audio/visual unsynchronized

When Wang is photographing the parking lot, the camera makes sounds as if it has a motor drive, but the camera clearly does not have one.

When Judge Smalls get hits in the groin, Danny tells him to "Walk it off, sir" but his lips don't move.

When Spalding is sneaking drinks during the dinner scene, you can see the guitar player in the background (on stage) is not in sync with the soft music the orchestra is playing.



Crew or equipment visible

The crew and boom are reflected in the car door when the red convertible pulls up on the tee box.



Errors in geography

The film supposedly takes place in Nebraska, but palm trees are visible as Danny is cycling to work during the opening credits.



Boom mic visible

In the scene at the beginning of the "illegal" match, when Ty and Al pull up in Al's car, you can see the boom mic visible as a reflection in the car door after Ty shuts the door (and slams his fingers in it).



Character error

When Al Czervik tees off after they've upped the bet, he's teeing off with a putter.

When Rodney Dangerfield's character takes over from the captain piloting his yacht,he may not have been legally allowed to do so. With small boat operation, the rules for operation of a ship are greatly simplified versus that of a larger motor vessel. For him to take over and run roughshod over the rules of right-of-way, not approaching shorelines and docks at speed causing wake damage and collisions, he would certainly have been fined and possibly been arrested for his reckless disregard of maritime rules.

In the first scene, when Mrs Noonan is waking everybody up, Michael O'Keefe tells his sister that Larry would return her training bra, he calls her by her real name 'Deb', her character's name is Kathleen.

When Judge Smails informs Spaulding that he's playing golf, rather than tennis, Spaulding argues, "What about my asthma?" Tennis is far more likely than golf to be affected by asthma.