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.
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.
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
Character mistake: In "Help Wanted", Stephen Hillenburg's name in the "Written By" section of the title card is incorrectly spelled as "Stephen Hilleburg."
Texas / Walking Small - S1-E18
Continuity mistake: In "Walking Small", The eel that stole Spongebob's ice cream cone throws it at his face. Different shots some show ice cream on Spongebob's nose, and some show that Spongebob's face is clean.
Sandy's Rocket / Squeaky Boots - S1-E8
Audio problem: In "Sandy's Rocket", when Sandy says "Aliens? Is that what this is about?" her mouth stops moving halfway into her sentence.
MuscleBob BuffPants / Squidward, the Unfriendly Ghost - S1-E11
Plot hole: In MuscleBob BuffPants, when SpongeBob first shows off his new inflatable muscles to everyone on the beach, he had the strength to punch two muscular fish into the air with them. A minute later, he could not even lift a glass of juice with the inflatable muscles. (00:04:25 - 00:05:20)
Scaredy Pants / I Was a Teen-age Gary - S1-E13
Continuity mistake: When Spongebob is cutting his Jack-O-Lantern, he cuts out an eye on his right, but in the shot from inside the pumpkin the eye hole is gone, then the eye reappears.
Bubblestand / Ripped Pants - S1-E1
Continuity mistake: Bubblestand: When SpongeBob comes out of his house at the beginning, he leaves his front door open. Later on, when Patrick's rock opens up, the front door to SpongeBob's house is completely missing. Then, when SpongeBob hands Patrick the bubble wand, the door is back, and it is now closed. Finally, when SpongeBob and Patrick walk into the house later on, the door is open again. (00:02:30)
Bubblestand / Ripped Pants - S1-E1
Character mistake: Ripped Pants: During the opening credits, Paul Tibbitt's name is misspelled as "Paul Tibibitt" (it is spelled correctly the second time it is shown), and Mark O'Hare's name is misspelled as "Mark O'hare." (00:11:54)
Hall Monitor / Jellyfish Jam - S1-E7
Continuity mistake: Hall Monitor: When SpongeBob sees the open window to the house, the window is opened to the left. When the two fish run out of the house after SpongeBob scares them, the window is opened the opposite way, then reverts back in the next shot. (00:05:19)
Continuity mistake: Rock Bottom: When the cardboard version of Spongebob next to the candy machine is shown, it is frowning, but it turns into a smile when it falls over. (00:18:48)
Sandy's Rocket / Squeaky Boots - S1-E8
Audio problem: When SpongeBob captures Mrs. Puff, her voice and the inflation sound are out of sync.
Continuity mistake: Rock Bottom: After SpongeBob and Patrick enter the bus, when SpongeBob asks Patrick if he has any change and for the duration of this shot, both the gear shift on the floor beside the driver and the open door of the bus have vanished, then they reappear.
Hooky / Mermaid Man and Barnacle Boy II - S1-E20
Continuity mistake: Hooky: When SpongeBob is hooked the pointy tip of the hook is facing out, but when he asks Krabs what he should do, the hook is hooked into SpongeBob's pants the opposite way, with the pointy tip facing him. Additionally, he's hooked at the back of his underwear and pants, but when Squidward is holding the fishing pole the hook is at the front of the underwear, which are also perfectly intact despite being ripped off SpongeBob.
Fools in April / Neptune's Spatula - S1-E19
Continuity mistake: Fools in April: While Squidward is having difficulty apologizing to SpongeBob, they're both standing in front of the pineapple with its front door wide open inward, but when Squidward places the bubble over his head the front door is suddenly wide open outward, so Squidward could slam the door.
Valentine's Day / The Paper - S1-E16
Continuity mistake: The Paper: The front door of Squidward's house repeatedly switches between opening at the right side and opening at the left side, and the round door knob also changes to a door handle as well, but then reverts back to the round knob.
