A 100% deposit bonus is a promotional offer commonly used by online casinos and sportsbooks, where the operator matches a player's initial deposit amount up to a specified limit. For example, if a player deposits $100, they receive an additional $100 in bonus funds, effectively doubling their bankroll. This bonus allows players to explore more games or place larger bets, but it often comes with wagering requirements that must be met before any winnings can be withdrawn. Understanding these terms is crucial for maximizing the benefits of the bonus.