Factual error: We hear Ace in the voiceover talking about Ichikawa, a guest at Tangiers, and Ace says, "About a year ago, he cleaned out a couple of casinos in the Cayman Islands." There have never been casinos in the Caymans. (00:19:10)
Continuity mistake: About an hour and a half through the movie there is a scene with Nikki on a black and white TV. On the TV they are showing a photo taken by police of Nikki talking to another man holding a toothpick to his mouth to cover his lip from lip readers. That scene takes place later in the movie. The police have not yet taken that photo, we see it happen later on. (01:32:49)
Character mistake: At their wedding reception when Ginger is talking to Lester on the phone he reminds her of when he watched her as a young "long legged colt." As a juvenile female horse she would have been a long legged filly.
Continuity mistake: When Sam is talking with Philip Greene after firing Ward, there is a shot of Sam facing the camera gesturing with his right hand not holding a cigarette, the a shot with his rear to the camera holding one, back to a shot facing the camera with empty hands again. (01:10:45)
Other mistake: When the man goes into the casino and takes a suitcase full of money to Kansas, he is parking in a supermarket. Later in the movie, after a plane lands on the golf course the same shot of the car in the supermarket is repeated. Check for the same parked cars: a blue VW beetle and a red car.
Audio problem: When Nicky is at the airport having his suitcase searched by Customs, he says "If you find any cash in there we'll whack it up with ya" but his lips don't move in unison with the sentence. (00:27:50)
Audio problem: When Pat Webb is reading aloud the newspaper article about Sam Rothstein, his lips don't match when he begins the sentence reading "the Midwest bookmaker", and also the audio sounds spliced in. (01:31:15)
Factual error: About a half hour into the movie, Nicky goes into the sports book to collect. There is a cigarette machine behind him and the price of a pack of cigarettes is marked $2.50 In the 70's a pack of cigarettes was more like one dollar. (00:33:04 - 00:33:35)
Continuity mistake: It is daylight when the car of Ace Rothstein explodes. However, it is night when he is being placed in the ambulance.
Other mistake: When Ace meets with Lester in the diner, Lester looks around at the guys guarding the exits. The camera pans around to show his perspective, looking first at the door directly behind him, and then the door to his right. Except the camera swings left for both shots, meaning Lester would've had to crane his neck around 270° to see the right-hand door while looking to the left.