Factual errors: The M4 used by Doyle when he is on the street level appears to have a PVS14 night sight mounted behind an EOTech holosight. However when the camera shot shows the view through the scope the cross-hair shape is not that of what would have actually been displayed using this sight combination.
Incorrectly regarded as goofs: During one scene, General Stone says that the Infection does not "cross species." However, the original outbreak began when humans came in contact with infected chimps. This is arguably because the US Army probably did not know the origin of the virus, and what General Stone said was based on the Army's observation after arriving in Britain.
Continuity: As a result of inconsistent computer editing, throughout the film, the logos on top of the HSBC and Citigroup buildings vary from being nonexistent to clearly visible.
Revealing mistakes: About half way into the movie: As the "infected" charge down the dark tunnel frantically because they are so full of rage, as they start to run down the stairs they all slow down, take small steps and grab the side rails to avoid falling.
Continuity: In the scene where the girl is in the pizza shop a window above the Greek Cuisine shop is open then shut in different shots.
Errori geografici: When the aircraft containing repatriated people approaches London, it is flying on to Runway 28 at London City Airport (LCY). When the passengers get off the aircraft they are at Stansted Airport and in the terminal buildings.
Errori geografici: The route the survivors took around London and the distances involved would not be possible in the time frame as shown in the film.
Continuity: In the scene when they are driving in the car to escape the toxic gas, the windshield is covered in blood, though in the next scene it is gone, then it reappears in the next shot.
Continuity: Flynn's helicopter changes multiple times. He is initially shown falling asleep in an Aerospatiale Gazelle. When he is attempting to rescue Doyle, he is flying an Aerospatiale A-Star. When he lands in the stadium to rescue Doyle and the children, he is flying an Aerospatiale Gazelle.
Continuity: When the helicopter is flying towards the cliffs over Dover at the end, all the fields are freshly plowed with short neat grass. Surely these fields would be wildly overgrown by now?
Factual errors: Scarlet wears her hair in a ponytail, which is an unauthorized hairstyle for a female soldier in an Army uniform. Females in uniform must wear their hair in a bun of some sort so that it does not hang down below their neckline.
Errori geografici: The DLR train carrying the settlers from the airport has "Greenwich" on the front destination, but that station is south of the river from Isle of Dogs and would not have been quarantined.
Factual errors: A Jubilee line train is seen on the platform at Charing Cross station in the showdown between Don and Scarlet. However, the Jubilee line has not run from Charing Cross since 1999, so access to that platform would be blocked off and it is not likely to have a train on the platform.
Factual errors: The virus is transferred via blood/body fluids, therefore in quarantine everyone especially the doctor should have worn goggles. In the surgery area scenes all they wore were surgical masks.
Revealing mistakes: When Don is running across the field from the farmhouse to the boat jetty you can see fresh tire marks in the grass from previous takes of the tracking shot of him being chased by the infected.
Continuity: When Andy is jumping on the trampoline, the grass is trimmed. But six months with no care would mean the grass would be overgrown and the trampoline would be covered in various debris.
Factual errors: Doyle decides to push start the car to help Andy, Scarlet and Tammy escape the gas. He makes this decision after repeated attempts to start the car using the starter motor (obviously audible in the movie). Push-starting is only useful in starting a car where there is not enough battery power to crank the motor with the starter motor itself. The battery was not flat as the motor could be heard cranking over, but with no ignition. In real-life push starting this car would have been futile.
Revealing mistakes: When the children are riding the motorbike through the cemetery, fresh flowers can be seen on one of the graves. Since the cemetery is outside the quarantine zone, there should be no-one around to visit the deceased.