Continuity mistake: When Roger and Peter are blocking the entrances with the trucks, Roger kills a zombie with a long beard that is walking towards him between the trucks. Later on in the movie, we see the same zombie, in the same clothes, outside the doors, trying to get in. (01:07:35 - 01:17:15)
Continuity mistake: In the beginning of the movie at the TV studio, Peter tells Fran that they are meeting at 9:00 to take a helicopter out of town. When they take off in the helicopter and fly away, there is a giant digital clock on a building in the background that reads 6:00. (00:05:05 - 00:18:50)
Continuity mistake: After parking the first truck in front of the mall doors, Roger jumps out and runs towards Peter's truck. Notice the zombie wearing the red and black striped rugby shirt. After Roger runs past him, he breaks zombie character and becomes concerned about his shirt being tucked in. (01:00:50)
Continuity mistake: Near the end, Steven is in an elevator, and the zombie opens the doors and starts biting him. When he gets them all out of the elevator, blood comes out of his mouth and down the right side of his face. But later the elevator doors open and Steven is a zombie and the blood is on the left side of his face.
Continuity mistake: When they stop to refuel the helicopter at the abandoned gas station, a zombie approaches from under an airplane. In one shot, it is holding onto the wing support next to it - in the next shot, the zombie is standing in front of the support with its hand at its side. (00:22:25)Phoenix
Continuity mistake: Watch when Sledge swings down from the balcony. In one quick shot, we see that there are two zombies in front of the store "Carlton's." When the shot changes to show Sledge landing, a third zombie has appeared from nowhere.