Something Smells / Bossy Boots - S2-E1
Continuity mistake: Something Smells: When SpongeBob walks into the kitchen the freezer door handle is on the right side, but when he opens the freezer door its handle is at the left side.
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.
SB-129 / Karate Choppers - S1-E14
Continuity mistake: SB-129: When Squidward opens the door to the time machine, the exterior side of the door has a handle at the left side and opens at the left, but the interior side of that door also has the handle at the left side, though it should be at the right side. Then when Squidward activates the machine, the exterior handle is now at the right side and it opens at the right.
Nature Pants / Opposite Day - S1-E9
Continuity mistake: Opposite Day: The front door knob on Squidward's house repeatedly switches between the left and right side of the door, so it opens the opposite way (it has nothing to do with it being opposite day).
Mermaid Man and Barnacle Boy / Pickles - S1-E6
Continuity mistake: Mermaid Man and Barnacle Boy: Mermaid Man wears green tights, but after SpongeBob absorbs the water ball like "some kind of evil sponge," when Mermaid Man and Barnacle Boy start doing the dog paddle, Mermaid Man's tights have vanished in this shot.
Mermaid Man and Barnacle Boy / Pickles - S1-E6
Continuity mistake: Mermaid Man and Barnacle Boy: When Barnacle Boy opens the box with the two rings inside, in the closeup the "B" ring is on the left and the "M" ring on the right, but in the wideshot Barnacle Boy removes the ring on the left (the "B") and places it on Mermaid Man's finger, then in the next shot we see it's the "M" ring, before both rings vanish.
Mermaid Man and Barnacle Boy / Pickles - S1-E6
Continuity mistake: Mermaid Man and Barnacle Boy: When SpongeBob and Patrick (dressed in their superhero costumes) exit the pineapple the front door opens at the right side (outward), but after getting on Squidward's nerves, when they retreat back inside the front door opens the opposite way at the left side (inward).
Dying For Pie / Imitation Krabs - S2-E6
Continuity mistake: Mr Krabs has no eyelashes when he tells Squidward not to tell Spongebob about the bomb he ate. (00:05:01)
FarmerBob/Gary and Spot - S12-E1
Continuity mistake: In "FarmerBob" when SpongeBob is taken to Old Man Jenkins' farm, after that, the next shot when he is stretched about 50m tall by a bag of potatoes, the tie is missing. (00:00:50 - 00:01:25)
A Flea in Her Dome / The Donut of Shame / The Krusty Plate - S5-E11
Factual error: In 'A Flea in Her Dome' Sandy opened up the door for water to fill her dome. The water even replaced the air on the inside which was above the door, which isn't possible because the air would have to go down through the door to escape the dome.
Grandma's Kisses / Squidville - S2-E9
Continuity mistake: When Spongebob and Patrick first arrive at the crowd, there's a window on the wall next to them. After they mistake that one octopus for Squidward, the window has vanished.
Driven to Tears/Rule of Dumb - S4-E17
Continuity mistake: In 'Rule of Dumb' Patrick's house returned to its former self in the outside shot just before Squidward's house was moved.
The Thing/Hocus Pocus - S4-E16
Continuity mistake: In 'The Thing' the house of Squidward's door first opened outwards, then later inwards. It also changes color.
Chocolate With Nuts / Mermaid Man And Barnacle Boy V - S3-E11
Continuity mistake: In 'Chocolate With Nuts' the bandaged up fish's house's front stairs had only a few steps when Spongebob and Patrick approached, but as the fish falls down there's suddenly a lot more.
Krab Borg / Rock-a-Bye Bivalve - S3-E8
Continuity mistake: In 'Rock-a-Bye Bivalve' Spongebob's front door changes hinge sides. Also at the end suddenly there's a light switch next to the door which wasn't there earlier.
The Secret Box / Band Geeks - S2-E14
Continuity mistake: In Band Geeks on day four the lever besides the big gate changes positions between pointing upwards and downwards several times.
Someone's in the Kitchen with Sandy/The Inside Job - S7-E3
Other mistake: In the kitchen when Plankton asks, "In approximately how long do you cook a patty?" Spongebob's eyelashes are missing.
Scaredy Pants / I Was a Teen-age Gary - S1-E13
Continuity mistake: Spongebob's belt is missing when his clothes are first revealed while dangling in midair.
Answer: In the "Christmas Who?" episode's intro, Patchy the Pirate is reading a letter where a fan ask if Spongebob loves Christmas as much as he does. Patchy explains they didn't always celebrate Christmas and this episode is a flashback to the first time Bikini Bottom had heard of Christmas. Santa had never visited before because nobody had believed in him before. Santa finally does visit because of Squidward's Christmas spirit. The "It's a Spongebob Christmas" episode aired 12 years later. So by this time, Bikini Bottom had been celebrating Christmas for quite sometime. Santa comes for a special visit because of how everyone in town, except Plankton, is on his naughty list.
Bishop73