Continuity mistake: When Pascal's henchmen infiltrate Buckingham Palace, and force the Queen to abdicate, if you look very closely on the abdication document it is dated the twentieth of March 2003. Yet in an earlier scene where Johnny English is photographed by the speed camera that has the date 21/03/03, obviously the abdication was filmed before the car chase, and therefore the dates get mixed up.
Factual error: When Johnny and Lorna are in the sushi bar, Lorna says 'cheers' in Japanese to Johnny before drinking Japanese sake. (An English subtitle is displayed). Johnny, obviously not knowing what he is saying replies in Japanese, and an English subtitle is displayed saying 'may all of your daughters be born with three bottoms'. The actual translation for what he says is 'May all of your daughters be born with a small penis'. (Not that any normal person would notice) (00:36:15)
Other mistake: In the chase scene, where Johnny and Bough are chasing the hearse, when Bough and Johnny are discussing where the hearse went, Johnny says "They were heading south." Then he turns the steering wheel to his right, yet when it shows a view of the truck it turns to it's left. (00:22:15)
Continuity mistake: When Natalie Imbruglia and Rowan Atkinson are trying to enter John Malkovich's "chateau", when Natalie is climbing a ladder a tattoo is visible on her lower back. Later, when Pascal Sauvage (Malkovich) is being crowned, Natalie is seen fighting a sniper on the upper-level of the church. When the sniper pushes her away, the tattoo on her lower back is gone.
Revealing mistake: At the start of the hearse chase, when we first see the bad guys pull a hand-brake turn through 90 degrees in a small London side-street, if you look on the ground you can see the skid marks from what must have been the previous take.
Factual error: When Johnny lands in the hospital instead of Sauvage's headquarters, there is a sign behind him which uses the American spelling of "Orthopedics" instead of the British "Orthopaedics."
Continuity mistake: When the DVD is put on during the coronation sequence, Johnny is holding the toothbrushes red above blue, while pretending to play the guitar. When the camera goes back to him, before he starts singing, the brushes have changed positions.
Continuity mistake: The first time the film of Johnny in the mirror is shown, look at the toothpaste in the bottom right corner. First you see the Aquafresh, then it cuts to Sauvage, and when it cuts back the toothpaste tube has moved. Then it cuts away and back again, and the toothbrush has moved in front of it.
Continuity mistake: In the scene where Johnny is in Sauvage's palace and drops down to take Sauvage prisoner, when the guards appear behind him the screen changes to Sauvage, and then back to Johnny, the guards have changed positions.
Continuity mistake: In the scene in the garage shortly before Johnny is about to "strike like a coiled viper" he talks to Bough via his wrist walkie talkie - only he talks into his RIGHT wrist while the walkie talkie is on his left.
Revealing mistake: When Johnny enters Sauvage's party, after he broke into his building, a waiter gives him a glass of champagne, which he drops. When a second glass is given to him, the pre-made crack on the paw of the glass is visible, prior to Johnny breaking that glass. (00:50:05)
Factual error: At the end of the film, after Johnny has foiled Sauvage's plot and the Queen has been restored, a news announcer says that Sauvage has been charged with high treason, which still carries the death penalty. Assuming the film is set in 2003, this is incorrect since the death penalty in Britain was abolished for all crimes, including treason, by the Crime and Disorder Act passed by Parliament in 1998.