You don't sign up for Medicare every year — but you do have a yearly window to change your coverage if you want to

Once you're enrolled in Medicare, you stay enrolled. You don't need to re-sign up annually just to keep your coverage active. However, Medicare has specific times each year when you can make changes to your plan — switching from Original Medicare to a Medicare Advantage plan, changing which prescription drug plan you use, or moving between Medigap policies. Missing these windows means you're locked into your current coverage for another year, with limited exceptions.

The key dates and rules depend on which type of Medicare coverage you have and whether you're making changes for the first time or switching plans you already hold. Understanding the difference between staying enrolled and making changes will save you from accidentally missing a important date or paying higher premiums when you switch later.

Key Takeaways

  • Once you enroll in Medicare, your coverage continues automatically each year without you having to re-sign up.
  • The Annual Enrollment Period (October 15 to December 7) is when most people can change Medicare plans or add prescription drug coverage.
  • If you miss the Annual Enrollment Period, you may have to wait a full year to switch plans, and you could face a permanent penalty on your premiums.
  • Certain life events — like losing employer coverage, moving to a new state, or getting married — open a Special Enrollment Period outside the annual window.
  • People new to Medicare at age 65 have an Initial Enrollment Period of seven months centered on their birthday month to sign up without penalty.

The Annual Enrollment Period: Your yearly window to change plans

Every year from October 15 through December 7, Medicare beneficiaries can make changes to their coverage. This is called the Annual Enrollment Period, and it's the main time you can switch between Original Medicare and Medicare Advantage, change your prescription drug plan, or switch Medigap policies. Changes you make during this window take effect January 1 of the following year.

You don't have to make a change during this period. If you're happy with your current plan, you can do nothing and your coverage will continue into the next year on the same terms. But if you want to switch — because your doctor is no longer in-network, your medications changed, or you found a plan with lower premiums — this is your opportunity. After December 7, you're locked in until the next October.

You can make changes online through Medicare.gov, by phone at 1-800-MEDICARE, or by mail. You don't need to contact your current plan to leave it; Medicare handles the transition when you enroll in a new one.

Initial Enrollment Period: Signing up for the first time at 65

If you're turning 65 and enrolling in Medicare for the first time, you have a seven-month Initial Enrollment Period. It runs from three months before your birthday month through three months after. For example, if you turn 65 in June, your window opens in March and closes in September.

During this period, you can sign up for Original Medicare (Parts A and B), add a prescription drug plan (Part D), or choose a Medicare Advantage plan instead. If you delay signing up past this window without a valid reason, you'll pay a permanent penalty on your Part B and Part D premiums for as long as you have Medicare. The penalty is 10 percent of the standard premium for each 12-month period you were late.

If you're still working and have health coverage through your employer, you may be able to delay Part B enrollment without penalty — but you must have creditable coverage (coverage that's at least as good as Medicare). Talk to your employer's benefits office or call Medicare to confirm your situation before your Initial Enrollment Period ends.

Special Enrollment Periods: Changes outside the annual window

Life events can open a Special Enrollment Period, giving you 60 days to make changes to your Medicare coverage outside the October-December window. These events include losing employer health coverage, moving to a different state, getting married or divorced, becoming a U.S. citizen or legal resident, or having a significant change in income.

You must report the event to Medicare within 60 days of when it happened. If you're switching plans because you moved, for example, you have 60 days from your move date to enroll in a new plan. If you miss this window, you'll have to wait until the next Annual Enrollment Period.

Some plans also offer a trial period. If you switch from Original Medicare to a Medicare Advantage plan, you have up to one month to try it. If you change your mind, you can go back to Original Medicare without penalty during this trial window. This is one of the few times you can make a change outside the standard enrollment periods.

What happens if you miss the enrollment important date

If you don't make changes during the Annual Enrollment Period and you don't have a may have access to life event, you're locked into your current plan for the rest of the calendar year. You cannot switch plans, add prescription drug coverage, or change from Original Medicare to Medicare Advantage until the next October 15.

The only exceptions are medical situations. If your plan drops a drug you need from its formulary, or if your doctor leaves your plan's network, you may be able to request an exception. Contact your plan directly to ask about a mid-year change. These are rare and require documentation, but they do happen.

If you miss your Initial Enrollment Period when you first turn 65, the consequences are steeper. You'll pay a permanent 10 percent penalty on Part B premiums and a 1 percent penalty on Part D premiums for each year you were late. These penalties stay with you for life, even after you finally enroll.

Keeping track of your enrollment dates

Mark your calendar for October 15 each year. This is when the Annual Enrollment Period opens, and it's a good time to review your current plan. Check whether your doctors are still in-network, whether your medications are still covered at the same cost, and whether your plan's premiums have changed. Medicare sends a notice in the mail before October, but it's straightforward to miss, so setting your own reminder helps.

If you're approaching 65, note your birthday month and count back three months — that's when your Initial Enrollment Period begins. If you have a life event like a move or job change, write down the date it happened. You'll need it if you want to request a Special Enrollment Period.

You can also set up a Medicare account at Medicare.gov. Once you log in, you can see your current enrollment status, view your plan details, and get reminders about enrollment periods. The account also shows your claims history and lets you read your Medicare card.

How to make changes during enrollment periods

During the Annual Enrollment Period, you have three ways to make changes. Online at Medicare.gov is usually the fastest — you can compare plans side by side, see which doctors and pharmacies are in-network, and enroll in a new plan in one session. You'll need your Medicare number, which is on your Medicare card.

You can also call 1-800-MEDICARE and speak with a representative who can walk you through your options and help you enroll over the phone. This is helpful if you're not comfortable using the website or if you have questions about specific plans. The line is open seven days a week, and calls are free.

If you prefer to work on paper, you can request a printed enrollment form by mail. This takes longer, so it's best to start early if you choose this route. You'll fill out the form and mail it back to Medicare. Make sure to keep a copy for your records.

Frequently Asked Questions

Do I have to do anything to keep my Medicare coverage active each year?

No. Once you're enrolled in Medicare, your coverage continues automatically. You don't need to re-enroll or take any action to keep it active. Your premiums will be deducted from your Social Security check (or billed directly if you don't receive Social Security) unless you change your payment method.

What if I turn 65 in the middle of the year?

Your Initial Enrollment Period is seven months long, centered on your birthday month. If you turn 65 in June, you can enroll starting in March. You should sign up as soon as possible during this window to avoid a gap in coverage or a permanent penalty on your premiums.

Can I change my Medicare plan if I move to a different state?

Yes. Moving to a new state is a may have access to life event that opens a Special Enrollment Period. You have 60 days from your move date to switch plans. Contact Medicare or your current plan to report the move and explore plans available in your new state, since coverage options vary by location.

What's the penalty for missing the Annual Enrollment Period?

If you miss the Annual Enrollment Period and don't have a may have access to life event, you straightforward can't change plans until next October. However, if you missed your Initial Enrollment Period when you first turned 65, you'll pay a permanent 10 percent penalty on Part B premiums and 1 percent on Part D premiums for each year you were late.

Can I switch back to Original Medicare if I try Medicare Advantage and don't like it?

Yes, but only during your trial period. When you first switch from Original Medicare to a Medicare Advantage plan, you have up to one month to change your mind and go back without penalty. After that month, you're locked in until the next Annual Enrollment Period, unless you have a may have access to life event.