Continuity mistake: When Charlie Brown holds the door for Snoopy before the gang leaves to trick or treat, his costume doesn't have all the extra holes in it like it does in the scenes before and after.
Continuity mistake: When Linus mails his letter to the Great Pumpkin, it can be seen that the mailbox has no writing on it. On close-ups, "U.S. MAIL" is written on the side of the box. (00:07:20)
Continuity mistake: When the kids are looking through their bags to see what they were given, suddenly a new kid in a ghost costume suddenly appears with them saying he got a quarter - he wasn't with them before.
Continuity mistake: When Lucy awakens at 4:00 AM she checks on Linus and then puts him to bed. In some shots there's a window over Linus' bed, but in other shots the window has vanished, and there's only a shelf over the bed. (00:23:10)
Continuity mistake: The fence which Linus tries to shove the pumpkin through at the start of the show, loses planks from one side to the next. On one side, the fence (to Linus's right) has nine planks. When the view changes to the opposite side, this same section of fence now has only seven planks. (00:01:05)
Continuity mistake: When Snoopy arrives at the Halloween party, he slides down a set of curtains and then hides behind those curtains. In the same shot, Lucy approaches a tub of water atop which five apples are floating. When the shot changes, there are only four apples floating in the tub and Snoopy has now somehow gotten into the tub and is hiding under the water. The action is constant. How did Snoopy get from behind the curtain to under the water? (00:18:30)
Continuity mistake: After choosing their pumpkin in the patch, Lucy is seen walking through a fence via a missing plank. The view then switches to the other side of the fence. Linus attempts to shove the huge pumpkin through the fence, but it won't fit. We then hear Linus rolling the pumpkin to the far end of the fence after which Linus and the pumpkin come back into view. However, after initially trying to get the pumpkin through the fence, although we have a great view through the fence, we never see Linus or the pumpkin go past the missing plank. (00:01:10)
Continuity mistake: When Charlie Brown is with the others before he shows all the holes in his costume, he's holding it and it shows only 2 holes about where they should be. But then when he brings it up, it's covered in holes.
Continuity mistake: When Linus and Lucy are walking to the mailbox, he has a letter in his hand. For a couple frames this letter and his arm suddenly disappear before returning.
Continuity mistake: When Lucy and Linus return to their home with the huge pumpkin, the house's surroundings are changed from what was seen just moments earlier at the beginning of the show. A bush next to the steps has gotten smaller and there is now a walkway leading to the house. (At the beginning, there seems to be nothing more than grass outside the front of the house.) Also, a tree, a garage, a telephone pole, a second house and a garbage can which they walked past at the start of the show, are not there when Lucy and Linus return home. (Though their own house steps have changed when Lucy and Linus return, it may simply be that they are now in shadow as the sun has, by then, gone down in the sky significantly.). (00:01:30)
Continuity mistake: When Snoopy approaches the pumpkin patch, crawling on all fours, the moon is white, medium-sized and partially up in the sky. When the shot changes to Linus and Sally, the moon is yellow, gigantic and touching the horizon. After Sally's disillusionment, the moon disappears from the sky. (00:21:15)
Continuity mistake: When Lucy and Linus exit their house to mail Linus's letter, the outside surroundings are different again. There is now the trunk of a huge tree in the front yard, a house in the background and a public mailbox just steps from their front door. (00:07:10)
Continuity mistake: When Linus is rolling the pumpkin, the position of the pumpkin goes from upside down to right way up between shots.
Continuity mistake: When Linus is rolling the pumpkin on the path, the path is plain, but when we see Linus following Lucy in the next shot, the path is slated.
Continuity mistake: When Linus and Lucy are heading to the pumpkin patch at the beginning of the film, Linus takes his blanket with him, but when they pick up a pumpkin and march back, Linus no longer has his blanket.
Suggested correction: When they get to the pumpkin patch, Linus drops his blanket. When they leave, he leaves his blanket at the pumpkin patch. He might have forgotten it, but it's not a mistake.