A First Deposit Bonus Bet is a promotional offer provided by online betting platforms to attract new customers. When a user creates an account and makes their initial deposit, the platform matches a percentage of that deposit, often in the form of bonus funds or free bets. This incentive allows newcomers to explore the site and place bets without risking their own money entirely. However, it's essential to read the terms and conditions, as there may be wagering requirements and restrictions on how the bonus can be used.