The Bikini Bottom Jail, also known as the Bikini Bottom Prison, is a governmental institution in Bikini Bottom that first appears in the episode "Hall Monitor."
The building is two stories high, with an oversized ball-and-chain attached to it. The prison features a rock-crushing yard, a cafeteria, and the jail cell. The building is composed of metal and is sky-blue with a black roof, on top of which has a brown wooden sign hold together by two bamboo sticks that reads the jail's name in white text outlined by red.
The inmates do many activities, such as crushing rocks, lifting weights, and making wire coat hangers and license plates.
Mrs. Puff has been in jail in "Hall Monitor," "No Free Rides," "Doing Time," "Ditchin'," and "Summer Job." In "Hall Monitor" and "Doing Time," Mrs. Puff was sent to jail because SpongeBob destroyed Bikini Bottom. In "No Free Rides," she stole SpongeBob's new boatmobile and crashed it into a police car. In "Summer Job," she was going to be sent to a Stoney Lonesome in the same outfit as "Hall Monitor." In "Ditchin'," she was sent to jail because she skipped Jury Duty.
It is also implied that she would go to jail in "Patrick-Man!" Patrick thinks she is breaking into a boatmobile, when in reality, she is trying to help one of her students who is locked inside and couldn't get out. Patrick throws a net over her and leaves a note that reads "Kops-This is boat theef." She is thrown into a paddy wagon, and one of the police asks if she remembers what a felony is.
She is also shown to be arrested in "Bumper to Bumper" after violating house arrest.
"The String" - Bikini Bottom Jail was presumably destroyed when SpongeBob unraveled all of Bikini Bottom and the Milky Way with the string.
Although he has been arrested many times, Eugene H. Krabs has never actually been shown in jail. Same goes for Sandy, who has only been arrested once (twice in a deleted scene) so far, but was never seen in jail.
Gary the Snail is the only main character who has never been arrested.
In "Summer Job," it is shown that SpongeBob teaches boating lessons at the jail.
A whale prisoner who looks similar to Pearl appears in jail in the episode "Jailbreak!"