Enrollment for Medicare isn’t always open. You first become eligible for Medicare three months before the month of your 65th birthday. Your initial enrollment period lasts for 7 months surrounding your 65th birthday and includes: · Three months before the month of your birthday · The month of your birthday · Three months after your birthday month For example, if you turn 65 in May, your Initial Enrollment Period would start in February and end in August. You can apply for Medicare Part A at any time after you turn 65. If you don’t sign up for Medicare Part B during your Initial Enrollment Period, and don't have creditable coverage, like through an employer, you will likely be required to pay a late enrollment penalty when you sign up later, which you will pay for as long as you have Medicare Part B. Because of this, it’s important to apply for Medicare when you’re first eligible.