Continuity mistake: Ethan shoots the glass on the front of the black bike during the chase near the end, but when the bike lands after jumping off the rock over Ethan, the glass is back in perfect condition.
Continuity mistake: In the first car chase, in the clip right after Nyah says '. you gotta catch me', you see the double yellow lines on the road. But in previous clips, and on the clip right after, the lines on the road are white. The clip with yellow lines are from another stretch of road.
Continuity mistake: In the final fight scene between Hunt and Ambrose, Ambrose cuts Hunt's face and back with his knife. But in the scene when the knife is close to his eye, you get a close up of it and there is no blood on the knife blade. It is perfectly clean.
Factual error: The aeroplane at the beginning of the film is a 747-400. You can tell because the wings had winglets when they showed the exterior view. Well, a 747-400 only has a two man cockpit, there is no "sideways flying" flight engineer like in the movie.
Continuity mistake: The agreed ransom at the start of the film is £37 million. Later this turns into 30 million pounds (though I may have got the share options bit a bit confused here). Then when the transfer is actually made, it has reduced to 30 million dollars.
Continuity mistake: When Tom and Thandie are lying in bed after the chase, at the end of the scene, he leans in to kiss her. Thandie brushes back a very clear lock of hair that has come out of nowhere.
Continuity mistake: In the rock climbing scene at the very beginning of the film, you can see the magnesium dirt left on the rocks from the earlier takes.
Continuity mistake: When Nyah is informed that the disc is in an envelope in Sean's pocket, she takes it out and puts it under her arm with part of it sticking out on the back side of her arm. The scene changes to a half body shot of Nyah and you can tell there is no envelope under her arm and as she turned to walk away Sean would have seen the envelope sticking out from under her arm.
Other mistake: Luther tells Ethan that he will only have 40 seconds for the louvres to remain open for him enter the ventilation shaft at Biocyte before the alarm goes off. But the warning message on Luther's computer says that the limit is 20 seconds. (01:06:30 - 01:09:10)
Revealing mistake: When Ethan's pal is in the helicopter and Ethan is escaping on the motorbike, he fires a grenade launcher at a gold ford Taurus driving across a bridge. When the grenade hits the car and the car explodes it flies into the air and off the side of the bridge. You can see as the car is falling from the bridge there's no engine or transmission in the car. It is only a shell.
Continuity mistake: At the end when the helicopter swings in front of the woman on the cliff, the damage to the left side of the helicopter is missing - bullet holes, broken glass etc.
Factual error: Near the end, Ethan Hunt and Sean Ambrose engage in a high-speed motorcycle chase that culminates with them crashing their motorcycles head-on. Just before the crash, both men leap off their bikes and their bodies collide in mid-air above the crash. However, if Hunt and Ambrose were racing towards each other at 40 mph (a conservative estimate), then the combined force of their bodies colliding would be equivalent to an 80 mph impact, which would pulverize their skeletons and kill both men instantly.
Continuity mistake: Near the start of the car chase at the end, a white car loses a hub cap in extreme close-up, but when it wipes out completely and flips over a few seconds later all its hub caps are still on.
Continuity mistake: During the end bike chase scene, Ethan Hunt has just used his mirror to fire his Beretta at Sean Ambrose, he then re-holsters the weapon and swerves round two cars. If you play the movie slowly you can see that after he re-holsters the gun it is still in his left hand while he is holding onto the handlebars. It's a quick shot so you have to look carefully.