The Chaperone / Employee of the Month - S1-E12
Continuity mistake: In "Employee of the Month", when Spongebob is spying on Squidward, Squidward puts his alarm clock to the left of his bed. When Spongebob tries to get the clock, it is now to the right of Squidward's bed.
Pressure / The Smoking Peanut - S2-E12
Continuity mistake: When Sandy and SpongeBob are climbing the mountain at the beginning of "Pressure," when Sandy pushes the rocks down at SpongeBob, there were two big ones holding them that vanish. You could say that she pushed them down too, but remember that they were different colours than the smaller ones. (00:01:40)
Sandy's Rocket / Squeaky Boots - S1-E8
Continuity mistake: When SpongeBob is explaining why he thinks there are aliens in Sandy's Rocket, you can see a plant and rocks. We see a wide shot and it has now disappeared. (00:02:00)
Something Smells / Bossy Boots - S2-E1
Continuity mistake: When Pearl gives SpongeBob the new costume for the Krusty Krab, she gives SpongeBob a mirror. In the mirror, Squidward appears and tells him not to accept the costume. If you notice, Squidward is at the LEFT of SpongeBob. Because is a mirror, in the real life he would be at the RIGHT of SpongeBob. When a shot is shown of SpongeBob and Squidward, you can see that Squidward isn't at the RIGHT of SpongeBob, he's at the LEFT.
Procrastination / I'm With Stupid - S2-E19
Continuity mistake: When Janet and Marty (Patrick's fake parents) let go of Patrick's hands in the living room, Marty is on the left. But when Janet and himself pat Patrick, his hand is to the right of Patrick.
Mermaid Man and Barnacle Boy III / Squirrel Jokes - S2-E4
Continuity mistake: In "Squirrel Jokes", right when he comes out of the curtains people put their hands up, but in a front view their hands are down.
Pizza Delivery / Home Sweet Pineapple - S1-E5
Continuity mistake: After Spongebob's house is gone, Squidward boo-hoos and goes into his house, then sounds happy. He starts throwing streamers and confetti out of his NOT-OPEN porthole. If the porthole was closed, they wouldn't fly out. Similar to some other ones in this show, and one in Fairly Odd Parents.
Culture Shock / F.U.N. - S1-E10
Continuity mistake: When SpongeBob and Plankton jellyfish,SpongeBob catches a jellyfish with no spots. Then it shows the jellyfish with spots or vice-versa.
Sandy, SpongeBob and the Worm / Squid on Strike - S2-E18
Continuity mistake: In "Sandy, Spongebob, and the Worm," the worm is about twice the height of Sandy and Spongebob. Near the end of the episode, the Worm charges off of the cliff and when he reaches the bottom, and smashes the town, the buildings are tiny compared to him and the sea creatures are microscopic.
SpongeBob Meets the Strangler / Pranks a Lot - S3-E20
Revealing mistake: In "Spongebob Meets The Strangler" when that fish holds up Spongebob's dry cleaning at the supermarket, it looks like he is holding it up with a coathanger because his hand is up in the air, but you can easily see nothing is holding it up. It's just floating up in the air.
Suggested correction: The clothes are being held up by a coat hanger. It may be hard to see due to it blending in with the wall color, but if you look closely, it's there.
Something Smells / Bossy Boots - S2-E1
Continuity mistake: When Spongebob is outside, and he takes out his "to do list" at first he is holding it with his right hand, but when it shows the front of the paper, you see that it is his left hand. Then it is his right hand again.
Sandy's Rocket / Squeaky Boots - S1-E8
Continuity mistake: When Pearl is opening her present the cake disappears.
Culture Shock / F.U.N. - S1-E10
Revealing mistake: In "Culture Shock" when Spongebob takes the green fish's order, he has a pencil tucked in his ear, but he doesn't have an ear, so it's just floating in thin air. (00:01:55)
The Sponge Who Could Fly (aka The Lost Episode) - S3-E16
Continuity mistake: On the news one fish had hair. Later it was gone.
No Free Rides / I'm Your Biggest Fanatic - S2-E10
Continuity mistake: After SpongeBob sees the "Queen Jellyfish" (really Kevin the sea-cucumber and his friends) he drops his jellyfish call out of his mouth. When it cuts to a wide shot, the jellyfish caller is nowhere to be seen.
Continuity mistake: In the scene where Mr. Krabs is saying "this is no game" Spongebob is in his underwear, then it goes to Mr. Krabs and back to Spongebob and he's in his work clothes.
Big Pink Loser / Bubble Buddy - S2-E3
Continuity mistake: It seems to me that half the cards that Spongebob used for the card snail have disappeared when Patrick comes in.
New Student Starfish / Clams - S3-E14
Continuity mistake: In the episode New Student Starfish., SpongeBob's good noodle stars changes number throughout the episode.
You Wish ('Shanghaied') / Gary Takes A Bath - S2-E11
Continuity mistake: After Squidward comments about how the ship is dirty, he continues to climb up the anchor rope. Once he's out of the shot, the rope immediately changes color.
The Graveyard Shift / Krusty Love - S3-E13
Continuity mistake: In "Graveyard Shift," when Squidward says to that guy they think is the hash-slinging slasher, "If that was you on the phone and you on the bus, then who was flickering the lights?" look at the "order here" sign. It says "order hear" instead of "order here," which it reads in previous shots during this episode.