Medicare Expert Q&A: What Happens if You Miss Your Medicare Enrollment Deadline?

Medicare expert Christian Worstell answers the question of how to sign up for Medicare if you miss your enrollment deadline.

In this Q&A series, Medicare expert Christian Worstell answers your questions about Medicare coverage, benefits, eligibility, enrollment and more. Christian is a licensed insurance agent and frequent contributor to

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"I recently turned 66 and will be getting ready to retire this coming January. Unfortunately, it looks like I missed my Medicare sign-up period. What happens if you miss your Medicare enrollment deadline, and what will I need to do now?" – Vance T., Bellingham, WA

Congratulations on your upcoming retirement, and thanks for writing to us. 

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Yes, you indeed missed your enrollment window known as your Initial Enrollment Period (IEP). Your Initial Enrollment Period began three months before your 65th birthday and ended three months after your birthday. 

Depending on several factors — mainly if you have group health insurance coverage through your employer —  the fact that you didn’t enroll during this period may or may not cost you money in late enrollment penalties.

  • If your employer has fewer than 20 employees and you didn’t enroll when you were first eligible, you may have to pay the Medicare Part B late enrollment penalty if and when you do eventually enroll.
  • If your employer has more than 20 employees, you may not have to pay a late enrollment penalty.

I assume that you – like most people working at age 66 – accumulated at least 10 years of working and paying Medicare taxes before you turned 65.

If so, this means:

  • You and your spouse qualify for premium-free Medicare Part A (hospital insurance).
  • You can apply for Part A coverage at any point after your Initial Enrollment Period started, and you won’t have to pay a late enrollment fee for your Part A coverage.

If you didn’t work pay Medicare taxes for at least 10 years, you may have to pay a monthly premium for your Part A coverage. If you have to pay for Part A and/or if you want to enroll in Part B medical insurance, you should sign up during your Special Enrollment Period.

Your Special Enrollment Period only lasts for 8 months, and it begins the month after you retire or the month after your employer health insurance coverage ends (whichever comes first). 

Assuming that your current employer health insurance coverage meets certain qualifications, you will be exempt from any of Medicare late enrollment penalties if you sign up during your Special Enrollment Period. 

Signing up for Medicare after your Initial Enrollment Period

I advise you to call 1-800 MEDICARE (here’s what to expect when you call) or visit your local Social Security office to speak with a representative from Medicare about your expected retirement date, how to sign up during your Special Enrollment Period and what actions you can expect to take when that big day finally comes. 

If you meet the requirements for a Special Enrollment Period, you can start the process of enrolling in Medicare online with the Social Security Administration.

Welcome to Medicare, and have a happy (and healthy) retirement!

One thing important thing to note: Medicare does not consider COBRA coverage or retiree health plans to be active employer coverage.

If you did not enroll in Medicare when you turned 65 because you were covered by COBRA insurance or a retiree health insurance plan, you will not be granted a Special Enrollment Period. You may be subject to late enrollment penalties if and when you do sign up for Medicare. 

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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.

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