At the beginning of Squid's Day Off, Spongebob rings the bell. But when Squidward complains that there is no customers, the bell disappears. But when Spongebob says "One Krabby Patty coming up", the bell reappears. But when the register drawer shoots open and hits Squidward, the bell disappears again.
In some of the scenes where Squidward runs towards the Krusty Krab, the five flags on the Krusty Krab have disappeared.
Near the beginning of "Squid's Day Off," Squidward says they won't have any customers because "No one comes in on Sunday." In multiple other episodes, it is stated that the Krusty Krab is not open on Sundays.
Squidward has eight tentacles when he dives underwater, but he actually has six tentacles.
"Emergency" is spelled as "Eneerency".
When Squidward tells Spongebob to stop ringing the bell, his legs become transparent for a single frame.
When Spongebob says, "Hopping clams!", his mouth is frozen.
The audio does not sync with the dialogue when Mr. Krabs says, "That's all".
Old Man Jenkins has a young man voice.
When Squidward runs past the emergency room, his nose appears to be smaller.