A signing bonus or sign-on bonus is a sum of money paid to a new employee by a company as an incentive to join that company. They are often given as a way of making a compensation package more attractive to the employee (e.g., if the annual salary is lower than she or he desires). It also lowers the risk to the company as it is a one-time payment; for example, if the employee does not meet expectations, the company has not committed to a higher salary. Signing bonuses are often used in professional sports, and to recruit graduates into their first jobs.
To encourage employees to stay at the organization, there are often clauses in the contract whereby if the employee quits before a specified period, they must return the signing bonus. In sports contracts, the full amount of signing bonuses is not always paid immediately, but spread out over time. In such cases, the main difference between a signing bonus and base salary is that the former is "guaranteed" money meaning the team is obliged to pay the bonus when due even if it cuts the player, unless the player retires or the contract is otherwise terminated due to a significant breach on the part of the player.