National Free Balloon Day is an event that the Bikini Bottomites celebrate annually, where balloons are sold for free. It is celebrated in the episode "Life of Crime" and the book Crime and Funishment.
Role in episode
SpongeBob and Patrick decide to "borrow" a balloon without permission and end up popping it. However, SpongeBob and Patrick then assume that they stole the balloon. As a result, they subsequently go to the police station to turn themselves in. However, they are paroled as soon as they came in with the policemen, particularly Officer Johnson and Officer Slugfish, informing them that they did not commit theft since it is Free Balloon Day.