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Key Deadlines for Medicare Enrollment

Know your timetable to avoid penalties and higher premiums

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Open enrollment to swap Medicare plans is Oct. 15 to Dec. 7, with a few exceptions.

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Medicare takes its deadlines seriously: Miss a key date, and you face penalty payments or higher premiums for as long as you are covered. Here are the dates to watch. 

Already on Medicare 

Open enrollment is from Oct. 15 to Dec. 7. With a few exceptions, such as a move out of state, you can only switch plans during this period. If you already have a Medicare Advantage plan, you can switch plans or change from an Advantage plan to original Medicare from Jan. 1 to March 31.

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New to Medicare

If you’re turning 65, aren’t getting Social Security benefits and don’t have employer-based insurance: You need to enroll in Medicare Part B during your initial enrollment period (IEP) to avoid penalties. Your seven-month IEP begins three months before the month you turn 65 and lasts until three months after. You should sign up for Part D drug coverage now, too, or face penalties later. 

If you’re turning 65, and already are getting Social Security benefits: You’ll be automatically enrolled in Medicare parts A and B; no action by you is needed. But you do need to apply during your IEP for a Part D drug plan, or if you want a Medicare Advantage plan instead of original Medicare. 

If you’re over 65, and retiring or losing employer-based coverage: You can sign up for Part B or an Advantage plan without penalty during your special enrollment period (SEP). This usually lasts for eight months after employee coverage ends. But you have only two months after losing drug coverage to sign up for a prescription drug plan before incurring a late penalty.

Last-chance options 

If you missed your IEP or SEP, you can still apply for Medicare coverages during the next general enrollment period, which runs from Jan. 1 to March 31. But coverage won’t begin until July, and you’ll be subject to late penalties. (Starting in 2023, coverage will begin the month after you enroll during the GEP.)

Editor's Note: This article, originally published on September 27, 2017, has been updated with new information.

Dena Bunis covers Medicare, health care, health policy and Congress. She also writes the Medicare Made Easy column for the AARP Bulletin. An award-winning journalist, Bunis spent decades working for metropolitan daily newspapers, including as Washington bureau chief for the Orange County Register and as a health policy and workplace writer for Newsday.

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