Like Plankton, Mr. Krabs has had many antagonistic schemes throughout the series. Most of them were plans to earn money. His plans have often led to failure with consequences such as his money being taken away.
- Arrgh!: Mr. Krabs gets SpongeBob and Patrick to be pirates and help him find the Flying Dutchman's treasure. The two eventually see that Mr. Krabs was using their game board as a map and that he wanted the treasure for himself. Note: This is the first time in the series to portray Mr. Krabs as a villain.
- Hooky: Mr. Krabs (along with Squidward) teaches SpongeBob a lesson and make him run home naked and laughs at him.
- The Smoking Peanut: Mr. Krabs steals Clamu's pearl thinking its "free" day. As a result, he is pelted on with peanuts by an angry crowd at the end of the episode.
- Patty Hype: Mr. Krabs takes over SpongeBob's business so he can earn money. The side effects anger the customers and they chase Mr. Krabs back and forth.
- Jellyfish Hunter: He tricks SpongeBob into collecting jellyfish. SpongeBob soon discovers that Mr. Krabs is squeezing jelly out of them so more jelly Krabby Patties can be made. The jellyfish are set free and sting Mr. Krabs all at once, burning his body.
- One Krab's Trash: Mr. Krabs tries to take back a soda-drinking hat he sold to SpongeBob after hearing about its price. He scares SpongeBob out of it with a paper ghost and fights an army of skeletons to get it back, only to find out it was worthless.
- Clams: Holds SpongeBob and Squidward hostage to get back his dollar from a giant clam.
- Born Again Krabs: Tries to sell a rotten Krabby Patty to customers. He gets sick after eating it and is persuaded to be generous by the Flying Dutchman. However - after realizing it wasn't a dream - he stole back toys from children, soda from a customer, stopped another customer from watching free TV, nearly rips someone's arm off for a penny, and trades SpongeBob for 62 cents.
- Krabby Land: Creates a bogus theme park and masquerades as a clown so he can collect children's' money. SpongeBob calls him cheap, and the children beat him up after finding out.
- The Krusty Sponge: Mr. Krabs makes "SpongeBob" (Actually Squidward in a SpongeBob Costume) cook "spongy patties", which made the customers ill and brought Mr. Krabs to court.
- Penny Foolish: Mr. Krabs sees SpongeBob picking up a "penny" and tried various plans to take it from him, even to the point of digging holes in SpongeBob's yard.
- Patty Caper: Tries to put SpongeBob in jail because he thought he stole it. He steals the secret ingredient of the secret formula, so he would not have to pay for delivery. As punishment, he was forced to sell free Krabby Patties all day.
- Plankton's Regular: Tries to steal Plankton's secret ingredient for Chum.
- Krabby Kronicle: Creates a newspaper and makes SpongeBob write lies about people, ruining their lives. Soon Mr. Krabs' scheme is found out, and an enraged crowd steals his money.
- The Slumber Party: Makes SpongeBob spy on Pearl and her friends. Pearl's party is ruined and Mr. Krabs is forced to spend his money for a new party.
- Krusty Krushers: Puts SpongeBob and Patrick in danger of being killed by huge wrestlers so he can earn the 1 million dollar prize. However, at the end of the fight, SpongeBob and Patrick choose wrestle camp instead, much to Mr. Krabs' dismay.
- No Hat for Pat: Made a fortune when Patrick kept falling on his face, disappointing SpongeBob. Eventually, people take their money back after a Patrick stunt failed.
- Greasy Buffoons: Mr. Krabs and Plankton sell customers greasy food. This eventually turns people (including Patrick) into overweight, mindless zombies. SpongeBob calls a Health Inspector, resulting in the Krusty Krab and the Chum Bucket being shut down.
- One Coarse Meal: Dresses up as a whale and terrorizes Plankton for about 17 days. NOTE: This is widely considered to be Mr. Krabs' most villainous role yet. He scares Plankton into being too scared to eat his dinner, having nightmares, and even trying to commit suicide.
- The Cent of Money: Uses Gary as a coin magnet. He steals peoples' money, brings Gary to exhaustion, and distracts SpongeBob by giving him tedious chores. Mr. Krabs is soon crushed by a tidal wave of money and put in the hospital, where every cent he collected is used up to pay his bill.
- The Wreck of the Mauna Loa: Gives away SpongeBob and Patrick's secret by turning it into an amusement park ride. He nearly gets everyone killed, and he gets arrested.
- The Masterpiece: Plans to become rich by making a giant statue of himself.
- Drive Thru: Creates a drive thru window in hopes of making money faster. He creates more drive thrus throughout the Krusty Krab which eventually leads to SpongeBob and Squidward desperately feeding more customers.
- The Googly Artiste: Sells Patrick's "art" for $50 a piece.
- The Krabby Patty That Ate Bikini Bottom: Creates a giant Krabby Patty in hopes of selling it but ends up getting eaten by it.
- Fiasco!: Tries to pay for customers to see the art but could not. At the end, he managed to get customer's money by showing the art through Patrick's belly.
- The Good Krabby Name: Has SpongeBob (and also Patrick) advertise all over Bikini Bottom so he can have every person eat at the Krusty Krab.
- Hello Bikini Bottom!: Makes himself the band manager of SpongeBob and Squidward. He even sells The Krusty Krab in hopes of making even more money with the band. He does not know that this will make him poor and out of business, and buys it back with Gary's college money.
- Safe Deposit Krabs: Mr. Krabs goes to the bank to get free money. Next, since he is not allowed, he went to the Safe Deposit area to get a lot of money.
- Yeti Krabs: Mr. Krabs tells a scary story to SpongeBob and Squidward so that they will work faster and make Mr. Krabs more money faster.
- SpongeBob You're Fired: Mr. Krabs fires SpongeBob in order to save a nickel. He also installs a pay toilet so customers have to save 5 cents to go to the bathroom.
- What's Eating Patrick?: Mr. Krabs forces Patrick to enter the food-eating contest or else he will be charged for all the patties he ate.