Continuity mistake: After the scene where Klebb arrives via helicopter on Spectre island and meets Morzeny, they enter a training area and continue their conversation while walking through it. Just after Morzeny says '.we use live targets as well,' the scene cuts to a wide shot and they are entering the same training area once again, only this time from a path that is just right next to the one used before.
Continuity mistake: When the man from Q branch shows the briefcase to Bond, he removes one of the ammunition sleeves from the case, opens it, slides a few rounds into his hand and then starts to return the rounds to the sleeve. Just before the cut to the throwing knife coming out of the case, Bond is still trying to put the rounds back into the sleeve, with the cap of the sleeve being held between his thumb and first finger of his right hand. At the cut, all the bullets have been replaced and the cap is back on the sleeve. When it cuts back to the wide scene, the cap is off again and Bond is now holding it in is left hand.
Factual error: When Bond arrives in Istanbul, the opening shot for the scene shows him arriving on the American-based Pan Am flight. Pan Am, or any American-based airliner, would most likely not have a flight going from London, UK to Istanbul, Turkey. Bond would have been most likely taking either a British-based airliner or a Turkish-based airliner. This error is more or less heavy handed product placement that wouldn't really happen in the real world, unless Bond flew from London to New York to Istanbul and that certainly would never be approved by a British government agency for one of its employees.
Continuity mistake: When Bond is in the gypsy camp, the two girls Vida and Zora, who are about to fight over a man, are coming out of a caravan both wearing long skirts and scarves. When they each take their scarf to bind it around their hips, the skirts have suddenly disappeared without ever being taken off.
Continuity mistake: When James encounters Tatiana for the first time in the bedroom of the hotel bridal suite, as he begins to sit on the edge of the bed he is holding his Walther in a non threatening position in the palm of his hand, with his thumb on top of the slide. As the scene cuts to the POV of Tatiana, the pistol is being held in a firing position, finger on the trigger, and switches back when the scene cuts back to the wide shot of both of them. Also when Tatiana reaches to move the gun away from pointing at her and says "Guns upset me" she returns her hand to beside her on the bed. At the cut to the wide scene, she is again moving the gun away.
Visible crew/equipment: When James Bond shoots down the helicopter then it crashes, he emerges from the rocks to run from the crash site to the right of picture, just as you see Sean Connery emerge from behind rocks from the right in the same scene. So for about a second there are two James Bonds in picture. One is the stunt man and the other is Sean Connery.
Continuity mistake: The train is stopped because Spectre has pushed a 1950's style Dodge truck full of flowers in the trains path. Later, when James is driving it trying to avoid the grenades dropped from a helicopter, the truck has turned into a very different looking 1961 Chevrolet truck.
Continuity mistake: Just after Grant has hit 007 on the back of his head and knocked him out, Grant searches through the pockets of 007, he takes out some money and puts it into his lower left side pocket. But when 007 kills Grant and searches his pockets, 007 takes back the money from Grant's inside top right hand pocket.