If you already get benefits from Social Security or the Railroad Retirement Board (RRB), you automatically get Part A and Part B starting on the first day of the month you turn 65 (if your birthday falls on the first day of the month, Part A and Part B will start on the first day of the previous month).

If you’re under 65 and disabled, you’ll automatically get Part A and Part B after you receive Social Security disability benefits or certain disability benefits from the RRB for 24 months.

If you have ALS (amyotrophic lateral sclerosis, also called Lou Gehrig’s disease), you’ll automatically receive Part A and Part B the month your Social Security disability benefits begin. If you are automatically enrolled, you will receive your red, white, and blue Medicare card in the mail 3 months before your 65th birthday or 25 months of disability benefits. If you do nothing, you’ll keep Part B and have to pay
Part B premiums through your Social Security benefits. You can choose not to keep Part B, but if you decide you want Part B later, you may have to wait to sign up and pay a penalty as long as you have Part B.

Important Note

If you live in Puerto Rico and receive benefits from Social Security or the RRB, you will automatically get Part A on the first day of the month you turn 65 or after receiving disability benefits for 24 months. However, if you want Part B, you will need to enroll by completing an “Application for Enrollment in Part B Form” (CMS-40B).

Manual Enrollment

If you’re close to age 65 but don’t get Social Security or Railroad Retirement Board (RRB) benefits, you’ll need to sign up for Medicare by contacting Social Security 3 months before you turn 65, or you can apply online. If you worked for a railroad, you will need to contact the RRB. In most cases, if you don’t sign up for Part B when you’re first eligible, you may have a delay in getting Medicare coverage in the future (in some cases, more than a year), and you may have to pay an enrollment penalty as long as you have Part B.

If you have End Stage Renal Disease (ESRD) and want Medicare, you will need to register. Contact Social Security to find out when and how to sign up for Part A and Part B.