Continuity mistake: When Kim is kidnapped, she describes the man "Beard. Six feet. Tattoo right hand, moon and star." When Bryan listens to the tape in the jet, she says, "Mustache. Six feet. Tattoo on right hand, moon and star. Dad!"
Continuity mistake: In the scene when he is driving his daughter to the airport before she flies to France, it appears they are riding inside a late model BMW 5-Series. This is apparent by the tan leather interior and the double adjustable padded headrests and rear seat headrests. However, when they appear at the airport terminal, he is seen unloading the luggage from his personal car, a 2005 Nissan Sentra GXE with a basic gray cloth economy interior (Confirmed by the Features on the DVD release)
Continuity mistake: When Kim is up for sale, before Liam can see her face, her hair is combed, then over her face, then combed again.
Other mistake: In the scene at the construction site, the guy in front of Liam Neeson gets a card with the number 4. When we see him inside, he walks past the number 4 room.
Visible crew/equipment: At the end of the movie when Bryan is fighting the guy with the blades on the yacht, the part where Bryan jumps over the couch you can obviously see it's a stunt double. The stunt double looks Chinese, he has black hair and slim while Bryan looks bulky and has light brown hair.
Continuity mistake: When Bryan is interrogating the man using the electrical chair, he is seen taking off his tie. In the next shot, when he is grabbing the lever and pulling it down, he is wearing the tie, but in following shots the tie is gone again.
Continuity mistake: When Bryan rescues one girl from the construction site brothel, he steals a white Jeep Cherokee to escape. When his pursuers start shooting during the chase, a shot of the Jeep's rear shows both red tail light lenses are gone. But the very next shot showing the right side of the Jeep proves they are intact.
Continuity mistake: In the scene Brian and the guy that bought his daughter are fighting on the yacht. After he jumps through the glass and the guy starts fighting with his knife, he is swinging to try to hit Brian but hits a lamp shade. You can see in the scene after that the lamp shade is gone, but when the camera goes behind Brian you can see that it is back on.
Continuity mistake: In the scene where Bryan is interrogating Marko, he pulls out the picture of Kim in his left hand, then the scene changes to Marko's face when he spits on Bryan, the picture changes to Bryan's right hand (because that's obviously his right thumb), then the scene quickly changes back to Bryan holding the pic in his left hand.
Factual error: The weapon Bryan uses to kill the Albanian kidnappers is a Beretta 92FS (M9); it has a 15 round magazine, yet he fires 17 times without reloading.
Factual error: Bryan's hot wiring of the Volkswagen Golf is feasible, all except that he doesn't break the physical steering lock that would prevent him from turning the wheel. Old Volkswagens are quite difficult to break the steering lock, a sharp snap of the wheel does not break it as it's quite a bit more sturdy than a mere pin. Pulling at the wires does nothing to affect the steering lock, and the lock is shielded precisely to stop outside tampering. Not enough time had passed for him to achieve the task of removing the security. The scene shown is not a condensed montage scene, it's a complete scene from start to finish of what Bryan did to steal the car, and the steering lock was never broken.
Other mistake: When Bryan is replaying the conversation between him and Kim, as she was being kidnapped, you can hear parts of the conversation that happened before he started recording.
Continuity mistake: When Bryan meets his daughter in the restaurant and gets her a milkshake with three cherries, as the scene cuts from Bryan to his daughter and back, the whipped cream goes from being on top of the milkshake to melted and then back again to being on top.
Continuity mistake: When the spotter is organising with the girls to go to the party outside their apartment, behind him you can see a grey Peugeot 806 people carrier with nothing behind it. In the shot as he walks away, a dark coloured car has now appeared behind the Peugeot - not enough time had passed for that to happen.