What is the difference between a discretionary bonus and a non-discretionary bonus?

Answer from Monica, SPHR, SHRM-CP:

A discretionary bonus, as its name implies, is a bonus in which the employer has discretion as to whether to pay it and what amount it will be. In other words, there’s no promise or agreement that a discretionary bonus will be paid. A surprise holiday bonus is one example.

A non-discretionary bonus, on the other hand, is a promised bonus that the employee expects to receive if certain conditions are met. Non-discretionary bonuses include individual or group production bonuses, bonuses for quality and accuracy of work, retention bonuses, and attendance bonuses. These bonuses are typically used to motivate employees.

The most important thing to remember about non-discretionary bonuses is that when issued to a non-exempt employee, they must be included in the employee's regular rate of pay when calculating overtime.

*Content taken from HRSupport 6/2019