Continuity mistake: In "Suds" after Spongebob crashes through his bedroom window, the blanket is hanging over the side and is all wavy, but when he's in bed it's completely plain and doesn't hang over the sides.
Help Wanted / Reef Blowers / Tea at the Treedome - S1-E2
Continuity mistake: In "Reef Blowers," when Spongebob is flying back from the rope he is pulling, Squidward is nowhere to be seen. When the ocean is getting drained, Squidward is sitting on his porch.
Valentine's Day / The Paper - S1-E16
Continuity mistake: In Valentine's Day, almost at the end, Patrick smashes some presents with his foot. After a while, Sandy arrives with Patrick's present (a chocolate globe), and you can see that the presents have dissapeared.
Valentine's Day / The Paper - S1-E16
Continuity mistake: In "Valentine's Day", SpongeBob and Patrick arrive at the fair. They watch the fair. Patrick says "You bought me a fair?", and Patrick runs to the fair. When he starts saying, "Get out of my fair.", we see that SpongeBob is closer to the fair than he was before.
Nature Pants / Opposite Day - S1-E9
Continuity mistake: When Spongebob goes to answer his door, Patrick was obviously in front of the door. After Patrick says, "Spongebob doesn't like me anymore", it cuts to a different shot to show the outside of the front door, and Patrick has moved to the side of the door.
Continuity mistake: In "Sleepy Time" when the neighbours are crowded around Spongebob, Plankton is standing on the end of the bed. When the angle changes, he's gone. Then he jumps onto the bed before Patrick joins them.
Jellyfishing / Plankton! - S1-E3
Character mistake: In "Plankton" when Spongebob is in Plankton's lab, he says the ingredients in a Krabby Patty. He doesn't mention the secret sauce.
The Chaperone / Employee of the Month - S1-E12
Continuity mistake: Spongebob absorbs the pink punch making him look pink in 2 shots - one showing him squirting punch out of his nose, but a shot after that shows him yellow.
Jellyfishing / Plankton! - S1-E3
Audio problem: In "Plankton" in the beginning, when Spongebob is outside with Mr. Krabs, Spongebob laughs. His laugh sounds different that how it does in the rest of the show.
Jellyfishing / Plankton! - S1-E3
Audio problem: In "Jellyfishing", in the beginning, when Squidward walks out of his house with his bike, Spongebob says "Hey, Squidward" but his mouth is saying something different.
MuscleBob BuffPants / Squidward, the Unfriendly Ghost - S1-E11
Continuity mistake: When Patrick throws Squidward the watermelon, it lands on his torso and he falls down. When the camera goes back to Squidward, the watermelon is in his mouth.
Hooky / Mermaid Man and Barnacle Boy II - S1-E20
Continuity mistake: In the beginning of Hooky, there are about three boats with 3 fisherman in each. That means there would be 9, but later there are dozens.
Hall Monitor / Jellyfish Jam - S1-E7
Continuity mistake: Hall Monitor: After SpongeBob walks out of class the bell rings and he gets trampled, and when Mrs. Puff follows him outside the classroom door is wide open, but then the entire door suddenly vanishes.
Naughty Nautical Neighbors / Boating School - S1-E4
Continuity mistake: Boating School: When SpongeBob remembers that it's the day of the boating exam, the calendar reads "boating exam today," but then it reads "driving exam today."
Continuity mistake: In "Sleepy Time", Spongebob is driving a car in his dream. When he starts to drive faster, he sticks his tongue out on his left cheek. When he makes a left turn in the next shot, it's sticking out on the right cheek.
Jellyfishing / Plankton! - S1-E3
Continuity mistake: Plankton! When SpongeBob and Plankton are talking at night Plankton gives SpongeBob a golden spatula. When Plankton says he wants a Krabby Patty for his birthday SpongeBob drops it. Then when SpongeBob walks away, the spatula is nowhere to be seen.
Help Wanted / Reef Blowers / Tea at the Treedome - S1-E2
Continuity mistake: In "Tea at the Treedome", in one shot, Spongebob's pants are inflated, and in the next shot they're not.
Mermaid Man and Barnacle Boy / Pickles - S1-E6
Continuity mistake: In the episode "Pickles", there is a large fish named Bubble Bass. Although his name is Bubble Bass, the captions say his name is Bubble Bath. It is clear that Spongebob is saying "Bass" not "Bath", and his name is given as Bubble Bass in SpongeBob's Diner Dash.
Help Wanted / Reef Blowers / Tea at the Treedome - S1-E2
Continuity mistake: In "Help Wanted" Gary doesn't have eyelashes. In every other episode he does.
Suggested correction: So Gary not having eyelashes could count as an early design for him. It's common that characters and environments may undergo changes after a pilot. Not a mistake.
But Gary never had eyelashes.
Help Wanted / Reef Blowers / Tea at the Treedome - S1-E2
Revealing mistake: When Spongebob uses his binoculars, his teeth turn yellow for one frame.
