When Lincoln and Clyde leave the mall with Tanya, Clyde is wearing a green scarf. When Tanya falls over, Clyde is wearing a pink scarf. In the next shot, Clyde is wearing a green scarf again.
When the Loud family arrived at the mall, Luna is seen wearing her hat. But when Lincoln starts to come clean, Luna doesn't have her hat on.
On Lincoln's plans under his mattress, there are two pictures of Luna. One under "Mess Up Christmas Plans" and one under "Stop Trip to Miami", which was meant to be a picture of Lynn. Then in the close up shot of the "Stop Trip to Miami" plan, the picture of Luna is changed to a picture of Lynn like it should be.
After Lincoln got pied by Luan, he wipes some cream off his eyes, but still had cream on his face and shirt. Then after Lincoln got a towel from Mr. Coconuts, the amount of cream on him decreased.
When Lana informs Lincoln that Hops has fallen into a slump, Hops is visibly inflated. However, in the close-up of Hops that follows immediately afterward, Hops is not visibly inflated.
At the beginning of the film, Lincoln mentions that December 25 occurs on a Thursday. However, the priority mail sticker on his package has the date of December 20 on a Friday. December 20 cannot occur on a Friday if December 25 is on a Thursday in the Gregorian calendar. The former date occurred in 2014, while the latter date occurred in 2013.