When Honeyface is dancing, she removes her gloves before her dress. In the next scene, she is seen without her dress, but with her gloves.
In the last two shots of the scene at the first meeting between the men, Dean Martin is suddenly wearing a different tie.
When the Vegas Casino bosses meet with Duke Santos, the fireplace hearths are glowing before he enters the room, and are dull afterwards.
Danny and Tony are casing the Sands and sit down at the lunch counter beside an attractive woman in the white dress and stole. The blue water pitcher on a saucer in front of the woman suddenly turns into a basket of dinner rolls between camera shots.
When Danny Ocean is showing the other guys the five hotels on the scarf, in the overhead shot he is pointing with his right hand. When it cuts to show him from the front, he is pointing with his left hand.
The men of Ocean's Eleven are supposed to be war buddies from the 82nd Airborne during WWII. However, during WWII the US Army was segregated by race. Josh Howard talks about his experiences during the war while on patrol; since he's Black, he would have been assigned to the 555th Parachute Infantry Regiment, which was never sent overseas but instead became smoke jumpers in the Pacific Northwest. Therefore, Josh Howard would likely never have met the others, at least, not during the war.
At the garbage truck lot early in the movie, Vince mentions Josh's having been awarded the "DSM" (the Distinguished Service Medal). The DSM is the Army's highest non-heroism award for meritorious service, awarded almost exclusively to high-ranking career officers. Vince would have meant to say the "DSC", or the Distinguished Service Cross, the second highest award for valor in combat, after the Medal of Honor.
Bergdorf's (Richard Conte) body is stiff when he is lifted out of the coffin. Rigor Mortis sets in a few hours after the person is deceased and is completely gone in 18 to 24 hours. Since the scene occurs, at least, 30-48 hours later, his body parts would be as movable as if he had just died and he would have been limp and not stiff.
Duke proposes a deal for half the stolen money, but tells Danny: "30% of something is better than 100% of nothing."
At times during Josh's song accompanied by the harmonica-playing garbageman, the harmonica can be heard when he is holding it at least a foot from his mouth. However, in these shots, there is a second harmonica accompanist, partially visible on the far right side of the frame.
When Danny goes to the cashier he asks for $25 in chips and leaves with the chips. But he only hands the cashier a single bill. There are no $25 bills in circulation. He more likely asked for "20 five dollar chips" for which he paid for with a $100 bill.
Right after midnight on New Year's eve, it's now January 1st. Everyone is ringing in the new year and the power goes out in all the casinos. One man say's darn that power, that's the second time this month, It's only been about a minute into the new year and month of January, so the power couldn't have gone out for a second time "this month". This is not a goof as a month is defined as four consecutive weeks. It had been one month since December 1st and there could have been power outages in that past month.
When Josh is driving the garbage truck and is stopped at the roadblock, a law enforcement officer should have recognized that Josh was far too clean and well-dressed be a real on-duty garbage man. This is not a goof as there is no reason to assume all garbagemen were dirty 24/7 as well as the officer was barely even looking at Josh to notice. There was no reason for the police to suspect garbagemen to give Josh a second thought.
(at around 39 mins) Acebos' houseboy hands him a phone by the pool. Instead of walking off-screen he crouches behind a table, glancing at the camera as though unsure whether or not he's still in the shot.
Although Red Norvo accompanies Sam in the lounge at the Sahara, his name is on the marquee at the Sands.
Early on when we first see Beatrice talking to Danny, she takes two drags on an unlit cigarette and (naturally) exhales nothing.
When Danny Ocean and his crew are walking to the funeral home entrance, the purportedly concrete sidewalk they're walking on repeatedly buckles under their feet at one spot, revealing it to be made of wooden boards - not concrete.
At approx 48:34 Mushy O'Connors starts to say his line too early, he then stops then says it when it his queue.
After the power has gone out, the MC in one of the casinos tells his orchestra leader to keep playing Auld Lang Syne... on a working PA system.
When Sam Harmon is singing 'Ain't That A Kick In The Head', a trumpet solo is featured most prominently, but the jazz combo on stage has no trumpet player. Instead, there is a saxophonist who mimes his part.
When the main characters' voices are heard on the telephone at various points, the voices on the phone are not those of the principle actors.
The xylophone player only plays about half the notes heard in the performance.
While discussing the heist with his gang, Danny states that it takes exactly 1 minute and 38 seconds to sing Auld Lang Syne, and that this is critical to timing the length of the planned electrical blackout during which they will rob the casinos. However, at the time of the heist, the song is being played at a different tempo in each casino, which would throw the timing off making it impossible to coordinate a heist that relies on precise timing.
After the heist, Josh drives a garbage truck to pick up the stolen money. There are two men riding on the back of the garbage truck. Moments later, we see the garbage truck as it approaches a roadblock but now the two men are missing. The other 10 men of Ocean's Eleven were out heisting the casinos. Who these two extra men are and what happened to them is never explained.
When Roger goes to Tony Bergdorf's old appliance store, the new owner tells him Tony's in San Quentin. Roger asks to use the owner's phone and immediately calls Acebos to give him the news. But as he's overheard on Acebos's phone, Roger tells him that Tony is in prison doing a sentence of "1 to 5". As the store owner hadn't told him that, and he had had no idea Tony was even in prison, there was no way Roger could have known, or told Acebos, what Bergdorf's sentence was.
As veterans, everyone on the team would have their fingerprints on file with the FBI, yet nobody wears gloves while robbing the safes.
At the end of the meeting, Danny Ocean says they will be in Las Vegas the day after tomorrow. By that time, several of the gang have secured jobs and are known to their fellow employees. Back then, the mob ran Vegas so things were different than the present, but still.
The chest x-ray seen as Bergdorf is talking to the doctor is upside-down.
Sam Harmon jokingly says, "Repeal the 14th and the 20th Amendment. Take the vote away from the women and make slaves out of them." He's off by one, on both points: the 13th Amendment abolished slavery, and the 19th gave women the vote.
In the scene where Danny gives his mistress his room key, in the background a supposedly professional roulette dealer tries to spin the ball and fails. He snatches the ball out again and fails again. On his third attempt, he somehow makes the ball go around the rim as it should. The actor playing the dealer had apparently never thrown a roulette ball before.
When Sam first greets Bea, he calls her "Mrs. Oceans". Her last name (and her husband's) is "Ocean" - singular, not plural.
On New Year's Eve, one M.C. says it is 20 seconds to midnight, and then several seconds later, starts counting down from 20.