It’s a good idea.
For groups with fewer than 20 employees, Medicare is primary to the group health plan.
Since Medicare is primary, the group plan acts as a supplement to Medicare. For instance, for Part B services, Medicare will pay 80% of the bill and the group plan will pay the remaining 20%.
If an employee who is eligible for Medicare Part B does not sign up, the group plan can pay AS IF the employee has Medicare. This means an employee paying the full premium might be surprised to learn that the group plan only pays 20% of the bill, leaving the employee with the other 80%.
The application of this rule will vary by carrier.