Medicare Part B (Medical Insurance) normally covers one flu shot per flu season in the fall or winter.
All people with Medicare are covered.
Your costs in Original Medicare
You pay nothing for a flu shot if the doctor or other qualified health care provider accepts assignment for giving the shot, and the Part B deductible doesn’t apply. If you get your flu shot from a doctor who doesn’t accept assignment, you may have to pay an additional fee for the doctor’s services, but not for the shot itself.