In general, retention bonus is a payment or reward outside of an employee's regular salary that is offered as an incentive to keep a key employee on the job during a particularly crucial business cycle, such as a merger or acquisition, or during a crucial production period.
However, many enterprises also grant bonus to employees who have worked with them for longer periods. ERPNext allows you to configure Retention Bonus for employees which will alert the HR Manager (or any role as configured in Email Alert) on the event of an employee working for a particular period, say 5 years.
You can create new Retention Bonus here,
Human resources > Payroll > Retention Bonus
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