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Automatic Enrollment in Medicare
Do I You to Sign up for Medicare?
Some people are automatically enrolled in Medicare Part A and/or B. However, most people have to sign up for Medicare during their Initial Enrollment Period.
Some People Don’t have to Sign Up For Medicare
Whether you will automatically get Part A and Part B of Medicare depends on your circumstances.
You don’t have to sign up for Medicare if one of the following situations applies to you.
- If you’re already getting benefits from Social Security or the Railroad Retirement Board (RRB). Then you’ll automatically get Part A and Part B starting the first day of the month you turn 65. (If your birthday is on the first day of the month, Part A and Part B start the first day of the prior month.)
- If you’re under 65 and have a disability. Then you’ll automatically get Part A and Part B after you get disability benefits from Social Security or certain disability benefits from the RRB for 24 months.
- If you have ALS (amyotrophic lateral sclerosis, also called Lou Gehrig’s disease). Then you’ll get Part A and Part B automatically the month your Social Security disability benefits begin.
- Puerto Rico has special rules for Medicare Enrollment. If you live in Puerto Rico and get benefits from Social Security or the RRB, you’ll automatically get Part A the first day of the month you turn 65 or after you get disability benefits for 24 months. However, to get Part B, you’ll need to sign up for it by completing an “Application for Enrollment in Part B Form” (CMS-40B).
Most People Have to Sign Up For Medicare
If the above situations don’t apply to you, you’ll have to enroll in Medicare.
- If you’re close to 65, but NOT getting Social Security or Railroad Retirement Board (RRB) benefits, you’ll need to sign up for Medicare. Visit ssa.gov/benefits/medicare to apply for Part A and Part B. You can also contact Social Security 3 months before you turn 65 to set up an appointment. If you worked for a railroad, contact the RRB.
- If you have End-Stage Renal Disease (ESRD) and you want Medicare, you’ll need to sign up for it. Contact Social Security to find out when and how to sign up for Part A and Part B. For more information, see, “Medicare Coverage of Kidney Dialysis & Kidney Transplant Services [PDF].”
Automatic Enrollment Package
If you are automatically enrolled in Medicare, you’ll get a letter, booklet, and Medicare card in the mail 3 months before your 65th birthday or the 25th month of disability benefits.
TIP: Medicare Part A is free for most people, but Medicare Part B has a premium for most people. You can choose to keep Part A, but not part B, although there are fees involved if you decide to enroll in Part B again later!
Enrolling in Medicare
If you aren’t automatically enrolled in Medicare Part A and/or Part B, you’ll need to sign up.
The first time most people can enroll in Medicare is during their Initial Enrollment Period.
Your Initial Enrollment Period is seven months long and starts three months before the month you turn 65, includes the month you turn 65, and ends three months after the month you turn 65.
For example, if your 65th birthday is in April, your Initial Enrollment Period is from January through July.
If you miss your Initial Enrollment Period, you can sign up during the General Enrollment Period, which runs from January 1 through March 31 of each year. If you sign up during this period, your coverage will start the following July 1.
You may have to pay a late enrollment penalty for Medicare Part A and/or Part B if you don’t sign up when you’re first eligible, and you may not be able to enroll in coverage right away.
Lastly, you may be able to sign up for Part A and/or Part B during a Special Enrollment Period if you qualify. You may qualify for a Special Enrollment Period if you or your spouse (or family member if you are disabled) have group health coverage based on current employment or you’re covered under a group health plan through the employer or union of a family member.
Learn more about enrollment periods and late penalties.
Citation: Medicare and You Handbook 2023 [PDF]. Medicare.Gov. Welcome to Medicare package (automatically enrolled). Medicare.Gov.
Thomas DeMichele
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Some People Get Medicare Part A/B Automatically, but Many People Have to Sign Up
Most people are not automatically enrolled in Medicare Part A and Part B and have to sign up during their Initial Enrollment Period. The following are exceptions: If you’re already getting benefits from Social Security or the Railroad Retirement Board (RRB). If you’re under 65 and have a disability. If you have ALS (amyotrophic lateral sclerosis, also called Lou Gehrig’s disease). Meanwhile, Puerto Rico, has special rules for Medicare Enrollment.
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