Revealing mistake: When De Niro gets shot in the neck, his bald skin cap wrinkles considerably when he presses the wound with his hand. Confirmed by make-up artist Dick Smith in the making-of documentary. (01:40:00)
Revealing mistake: A crowd of people are watching the filming as Harry sprays one of the kidnappers with a water hose. (01:25:49)
Continuity mistake: In the scene where the German and Jewish drivers are arguing, there is a corner establishment visible in the background with a sign that reads "wash." In certain shots, a "going out of business" sign is visible in the storefront, while in other shots, with close-ups of two passers-by observing the argument, the same corner establishment is visible without the "going out of business" sign.