There are some limited circumstances when employers can hire employees who are under a certain age or institute a mandatory retirement age for employees. The age limitation must be based on a business necessity.
Most employers institute age limitations to protect public safety.
In such situations, there must be evidence that the limit actually protects public safety and there is no other way to effectively protect safety. For example, airlines may have a mandatory retirement age of 65 for pilots. In addition, employers may have mandatory retirement at age 65 for employees who have worked for two or more years in an executive or policymaking position. The employee must be eligible for a retirement or pension plan. Work with an experienced lawyer in your state.