Apart from losing points from a house, serious misdeeds at Hogwarts are punishable by detention. Whenever a student loses a house point, their house jewels (ruby for Gryffindors, emeralds for Slytherin, sapphires for Ravenclaw, and topazes for Hufflepuff) are taken away from a glass hourglass located in every classroom. The same goes for adding points to the specific house, although the teacher or prefect must conjure the gems from thin air.

According to the school caretaker, Argus Filch, detention meant subjection to various forms of corporal punishment until recently. Arthur Weasley claimed still to bear physical scars inflicted by Apollyon Pringle, Filch's predecessor. In present times, however, detention usually involves assisting staff or faculty with tedious tasks. Examples of detention include the one imposed on Harry by Umbridge in Order of the Phoenix. In this case, Harry was forced to write, "I must not tell lies" repeatedly using a magical quill which then carves what is written into the back of the writer's hand. However, most teachers at the school never use this cruel punishment. In another case, when Snape caught Harry using the Sectumsempra curse on Draco, he was forced to go through over a thousand boxes of files describing wrongdoers at Hogwarts and their punishments. Harry was supposed to order them in alphabetical order, and rewrite the cards whose words were hard to see or otherwise damaged. The Weasley twins Fred and George had a whole drawer of these cards.

For even more serious offences, students may be suspended or even expelled from Hogwarts. Harry and Ron are threatened with expulsion after crashing Ron's car into the Whomping Willow at the start of their second year, and Harry is expelled before the start of his fifth year (although the sentence is quickly changed to a disciplinary hearing) after he is detected using magic in the presence of Muggles, a serious offence among the wizarding community. Dumbledore argued in Harry's defence, stating that it was done in self-defence, and that the Ministry has no authority to expel students – such powers are invested in the Headmaster and the Board of Governors. Snape has attempted to have Harry expelled, and he attempted to have Harry's father, James Potter, expelled when they were at Hogwarts together. The only student known to have been expelled is Hagrid, for the murder of Myrtle with an acromantula believed to be the Monster of Slytherin and for opening the Chamber of Secrets – crimes for which Tom Riddle had framed him.

Professors seem to be able to punish students with relative impunity and can hand out detention, even for unsatisfactory grades. Enforcement of rules outside of class mainly falls to the caretaker, with the assistance of the prefects. A student's Head of House usually has the final say in disciplinary matters. However, during Umbridge's tenure at Hogwarts, she quickly obtains the power to have the final say in disciplinary actions, due to an Educational Decree (one of many) passed by Minister for Magic Cornelius Fudge.

In the summer before their fifth year, two fifth year students from each House are picked to be prefects, which grants them privileges and responsibilities and disciplinary responsibilities. The leaders of the student body, the Head Boy and Head Girl, are drawn from the seventh year students. Prefects have the authority to give detentions for infractions.