- "Once a champion has been selected by the Goblet of Fire, he or she is obliged to see the tournament through to the end. The placing of your name in the goblet constitutes a binding, magical contract. There can be no change of heart once you have become a champion."
- —A binding magical contract is absolute[src]
A binding magical contract is a natural, magically-enforced agreement between two or more wizards or witches who partake in it.
Putting a name in the Goblet of Fire formed such a contract. Those whose names were selected were obligated to compete in the Triwizard Tournament. Harry Potter apparently thought that he would be bound as a party to this contract, and he participated in the 1994 Tournament, despite the fact that his name was entered by someone other than himself. However, since he did not try to refuse to participate, he did not find out whether he was required by contract to participate.
Entry at the enchanted garden where the Wizarding Schools Potions Championship was held also constituted a binding magical contract. Those present were bound to participate, even if they arrived late to the start of the competition.
- Harry Potter and the Goblet of Fire (First appearance)
- Harry Potter and the Goblet of Fire (film)
- Harry Potter and the Goblet of Fire (video game)
- LEGO Harry Potter: Years 1-4
- Wonderbook: Book of Potions