Continuity mistake: In the scene where the man has DeNiro pull over to the curb and says he is going to kill his wife with a .44 gun, there is a close up of the meter clicking over to $2.75. In the next shot from the backseat, the meter reads $0.65.
Continuity mistake: During the fight in the end, Travis shoots a man's hand and his four fingers are blown apart; yet when the same man jumps at Travis as he enters Jodie Foster's room, you can briefly see two of his "missing" fingers on Travis' shoulder. (01:39:40)
Factual error: Travis begins the movie at 26 years old, and reports leaving the army with honorable discharge in May 1973. His first diary entry just after being hired is "May 10th." In the newspapers at the end he is still 26, and it says that he has been a taxi driver for 6 months. The movie obviously does not take place in winter, and the only months referenced (plus the timeline of a presidential nomination) are June and July. Besides, 1973 would not be the right year for a story set just before a presidential election, unlike 1976 when the movie came out.