General Enrollment Information

I have Medicare Part A and Part B. I’ve heard about Part C and Part D, but I don’t know what those are. Do I need to sign up for those during the Medicare Open Enrollment period?

Medicare Part C plans, also known as Medicare Advantage plans, are private health insurance plans, mainly HMOs and PPOs, for people enrolled in Medicare. If you enroll in a Medicare Advantage plan, you still have Medicare, but you get all of your Medicare-covered benefits through a private plan. Most Medicare Advantage plans also cover prescription drugs and most also cover other services, such as vision, dental, and hearing benefits. If you have Part A and Part B already, and are covered under the traditional Medicare program, you do not need to sign up for a Medicare Advantage plan during Open Enrollment unless you want to get your Medicare benefits through a private plan.


Medicare Part D is the Medicare prescription drug benefit which is offered by private stand-alone prescription drug plans, sometimes called PDPs, and Medicare Advantage plans that cover drugs. If you are covered under traditional Medicare and you want drug coverage, you can enroll in a stand-alone drug plan during the Medicare Open Enrollment period. If you did not sign up for a Part D plan when you got your Part A and Part B coverage and you do not have another source of drug coverage that is at least as good as Part D coverage, be aware that you may be charged a late enrollment penalty. Once you are enrolled in a Part D plan, you can switch drug plans during the Medicare Open Enrollment period.


To learn more about the Medicare Advantage plans and the Medicare Part D plans in your area, you can use the Medicare coverage comparison website, a searchable tool on the website. You can also call 1-800-MEDICARE (1-800-633-4227) or speak to someone at your local State Health Insurance Assistance Program (SHIP). SHIPs offer local, personalized counseling and assistance to people with Medicare and their families. You can call 877-839-2675 to get the phone number for the SHIP in your state.

While we have made every effort to provide accurate information in these FAQs, people should contact the health insurance Marketplace or Medicaid agency in their state for guidance on their specific circumstances.

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