When Mr. Glass gets his first comic book on the playground bench in 1974, the cover of the book depicts as a backdrop the Philadelphia skyline, featuring predominantly Two Liberty Place, which was not built until 1990.
At several points they show comic book images which are supposed to be from the "silver age", the 1950s-1960s. However, the art displayed in them is not accurate for the period and is closer to the style predominant in the industry in the 1990s.
Mr. Glass incorrectly describes his disorder (Osteogenesis imperfecta). He describes the disorder as having 4 types each increasing in severity. There are 7 types of the disorder and each type has a variety of severities.
David Dunn and a few other security guards are shown wearing FSU jackets and caps; this refers to the fictional Franklin State University where he works (the name derives from Franklin Field, the actual stadium name).
Appears to be a continuity error. Elijah as a boy in scene inside house has his right arm in a sling. When he goes outside to open his gift his left arm is in the sling and he uses his right arm to open gift. But in fact the scene inside the house is a reflection of Elijah in the TV Screen, so it is actually his left arm.
When David shares his identity with his son at the breakfast table, he pushes a newspaper toward him. In the close-up, the newspaper is folded into quarters, but in the wide-angle shot, it is clearly only folded in half.
When David's son attempts to shoot David to prove David is unbreakable, David grabs the gun from the table using his left hand (with his wedding band on) in the close up shot, but in the master shot, we can see he used his right hand to grab the gun.
When David follows the Orange Suit Man into the house, David goes upstairs and into a bedroom where he hears a whimper. In the master shot, the closet door where the children are held captive is cracked but in the following shot David is seen and heard opening the same door.
The burglar which David incapacitated is supposed to be dead according to the newspaper article. But after he was strangled and lying on the floor he was still visibly breathing. So either David killed him later or he died from the chocking later or the article was mistaken. All of these make little sense.