The film was rushed to theaters, leaving a few mistakes which Universal fixed. In the original cut, toward the end, Judi Dench's human hand is visible, complete with her wedding ring. This was fixed for the re-release.

When Mandy falls inside the Porsche, her stunt double is noticeable because she is way older than her.

During the General Patton speech before the football game, "Gill Harris" approaches a player wearing the number 19 on his jersey, who is black. During the football game you notice the player wearing number 19 on his jersey is now white. (00:45:45 - 00:47:00)

In the bridge fight scene where Colossus and Negasonic Teenage Warhead appear, Deadpool tries to escape Colossus' handcuffs by severing his hand. The hand that he cuts off is his left, but when he jumps off the bridge the severed arm is on his right side.

When Ingrid sits at the vanity table in the bedroom, in the shot just after Gregorio's screen reads, "Type password," but just before the close-up of Ingrid's fingers typing on her makeup, there is a lovely reflection of a crew member behind the camera, which is perfectly clear in the mirror to Ingrid's right. (00:07:30)

When Patch and his roommate are arguing about why he wanted Patch out of the college, the book on the desk changes to a very different looking book between shots - note the tabs and red-edged pages.

Kevin sits down with a meal before the Wet Bandits arrive at the house consisting of macaroni and cheese on a plate. When Harry eventually makes it to the dining room, he is pelted with feathers. Look at the table to the left. A three part microwave meal still in its white plastic container now sits on the plate.

Visible crew/equipment: During the chariot race, just as Judah (stunt double) flips over in his chariot in the wide shot, a low angle camera is visible on the track under a canopy, at the right side of the screen.

When John says, "You offend reason sir," Peter floats up. The large light fixture is hanging from the ceiling. However, in the next shot facing Peter when he says, "Just think happy thoughts," where is the light fixture? It's gone so Peter can fly around the ceiling, but it's back again in later shots. (00:21:15)

When Nicolas Cage drives through the window in the yellow Ferrari and the shot changes, he is coming out from a different window than in the first shot. In the first shot he emerges from the window to the left of the 7th Street Garage storefront ('Classic Autos' written on the window), but next shot he emerges from the window to the storefront's right. Also, note the now glassless window to the storefront's left, due to a previous take.

There's one bit where we see the shark slamming into a boat and gliding along the side with its mouth open. Not only does the shark's latex mouth bend beneath the snout, narrowing from pressure, but within the mouth you can clearly see yellow hydraulic tanks to open the mouth. (01:22:05)

During Quidditch tryouts, when Ron blocks the Quaffle with his head in the closeup, Ron's body disappears at the bottom of the screen below the digital editing line. (Only visible on fullscreen DVD).

In the scene in the basement, Chunk is about to drink from the water cooler bottle that is mostly empty. When he stands up and tries to catch it, it's more than half full. (00:40:25)