Q. Under our written company policy, an employee who fails to give 20 working days' notice before resigning forfeits any earned vacation days. Is this policy lawful? —C.R., Wisconsin
A. Yes, but by requiring employees to give 20 working days' notice before they leave, your company may compromise its position that it employs individuals on an “at will” basis. An employee could argue that the policy is a mutual promise that both the company and the employee are required to give such notice before ending the employment relationship.
You could institute an accrual policy under which vacation time is earned over the year, rather than granted at the beginning.