The Head Boy's Badge is a silver badge worn on the school robes of the student appointed to the position of Head Boy. The design is similar to that of a Prefect's Badge. Percy Weasley's badge is described as being made of silver. It featured the letter 'H' for Hogwarts and a scarlet banner beneath it, upon which the words “Head Boy” were inscribed.
The primary function of the badge is to serve as a visible symbol of the wearer's authority and status as the Head Boy of Hogwarts. While the badge itself is not explicitly stated to be enchanted with specific spells, it is intrinsically linked to the privileges of the office.
The Head Boy's Badge is part of a long-standing tradition at Hogwarts School of Witchcraft and Wizardry. Each year, one seventh-year boy is selected by the Headmaster to serve as Head Boy. Upon selection, the student receives the badge, typically via owl post along with their school letter before the start of the term. The badge is worn for the duration of the school year. It is presumably returned at the end of the year so it can be passed on to the next student appointed to the role. Notable former Head Boys who possessed this badge include Tom Riddle, who used the position to mask his nefarious activities, and James Potter, whose appointment surprised some given his reputation as a troublemaker.
The Head Boy's Badge serves as a significant symbol of achievement, responsibility, and ambition within the Hogwarts student hierarchy.