Medicare Expert Q&A: Will I Be Automatically Enrolled in Medicare When I Turn 65?

Medicare expert Christian Worstell explains automatic Medicare enrollment, including instances where Medicare won't let you know you need to enroll.

"I turn 65 next year. Will I be automatically enrolled in Medicare? Is there anything I need to do?" – Linda M., Springfield, MO

Thanks for writing in, Linda. I’ll start answering your question by asking one of my own: Will you be collecting retirement benefits from Social Security or the Railroad Retirement Board for at least four months by the time you turn 65 years old?

I ask because automatic enrollment in Medicare hinges largely on that particular criteria.

  • If you are already collecting Social Security retirement benefits or Railroad Retirement Board benefits (or if you plan to start receiving those benefits soon) for at least four months prior to turning 65, you will typically be automatically enrolled in Medicare Part A and Medicare Part B on the first day of the month in which you turn 65.

    In fact, you should expect to receive your Medicare card and a “Welcome to Medicare” packet of information in the mail in the weeks leading up to your 65th birthday.

    Medicare Part B is optional, but you will still be automatically enrolled and given the option of opting out later on, if you choose.

  • If you choose to delay collection of your Social Security or Railroad Retirement Board retirement benefits and will not be collecting those benefits by age 65, you will not be automatically enrolled in Medicare.

    If this is the case, you must take steps to manually enroll in Medicare. You can do so online at the Social Security Administration website, over the phone by calling 1-800 MEDICARE (1-800-633-4227) TTY 1-877-486-2048, or in person at your local Social Security office

Medicare typically won’t let you know that you need to enroll

It’s important to know that if you are not collecting Social Security or Railroad Retirement Board benefits and therefore are not eligible for automatic Medicare enrollment, Medicare will not take any steps to contact you or notify you of your enrollment options.

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If you do not enroll within three months after turning 65 (the end of your Initial Enrollment Period), you may be faced with late enrollment penalties and delayed coverage when you finally do enroll later on.

Enrolling in Medicare during your Initial Enrollment Period (IEP)

Let’s talk a little more about your Medicare Initial Enrollment Period. This period begins three months before you turn 65 years old, includes the month of your birthday and continues for three more months after you turn 65, for a total of seven months. 

Medicare IEP graphic

It is during this Initial Enrollment Period that you may first sign up for Medicare.

During your IEP, you may also be able to enroll in a private Medicare insurance plan such as:

  • A Medicare Advantage (Medicare Part C) plan that provides all the same benefits as Original Medicare (Parts A and B) but is offered by a private insurance company and may include additional benefits such as prescription drug coverage

  • A Medicare Prescription Drug Plan (Part D) that covers retail prescription drugs that Original Medicare typically doesn’t cover

Private Medicare plans are optional and you will not be automatically enrolled in any of them.

If you choose not to enroll in a Medicare Advantage plan or a Medicare Part D plan during your Initial Enrollment Period, you will have to wait for the Annual Enrollment Period (AEP, also known as the Medicare Open Enrollment Period for Medicare Advantage and prescription drug plans) that runs from Oct. 15 to Dec. 7 each year.

Medicare AEP graphic 

Applying for a Medicare Supplement plan after you turn 65

Depending on your eligibility, you may be able to apply for a Medicare Supplement Insurance (Medigap) plan after you turn 65.

A Medigap plan works alongside your Original Medicare coverage and helps pay for certain out-of-pocket Medicare costs such as copays, coinsurance and more. The best time to apply for a Medigap plan is during your Medigap Open Enrollment Period, which lasts for six months and starts as soon as you are 65 and enrolled in Medicare Part B.

It’s important to note that Medicare Supplement plans and Medicare Advantage plans are not the same thing, and you cannot have a Medicare Supplement plan and a Medicare Advantage plan at the same time.

Get help comparing Medicare Advantage plans where you live

If you have any additional questions about the Medicare Advantage plans that may be available where you live, you can call today to speak with a licensed insurance agent who can help you compare plan costs, find out what plans cover your drugs and – if you’re eligible – help you sign up for the right plan for you.

You can also compare plans online for free, with no obligation to enroll. 

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About the author

Christian Worstell is a licensed insurance agent and a Senior Staff Writer for He is passionate about helping people navigate the complexities of Medicare and understand their coverage options.

His work has been featured in outlets such as Vox, MSN, and The Washington Post, and he is a frequent contributor to health care and finance blogs.

Christian is a graduate of Shippensburg University with a bachelor’s degree in journalism. He currently lives in Raleigh, NC.

Where you've seen coverage of Christian's research and reports:

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