Medicare lets you switch plans during specific windows each year, not whenever you want

You cannot change Medicare plans at any time. Instead, Medicare has set periods when switches are allowed. The main window is Open Enrollment, which runs from October 15 to December 7 each year. During this time, you can switch from one Medicare Advantage plan to another, drop Medicare Advantage to go back to Original Medicare, or change your prescription drug plan. Changes made during Open Enrollment take effect January 1 of the following year.

Outside of Open Enrollment, you can only switch plans if you have a may have access to life event — a specific change in your circumstances that Medicare recognizes. These events open a Special Enrollment Period, usually lasting 60 days, during which you can make changes. If you miss both the annual Open Enrollment and any Special Enrollment Period you may have access to for, you are locked into your current plan until the next October.

Key Takeaways

  • Open Enrollment runs October 15 through December 7 each year, and any Medicare beneficiary can switch plans during this window.
  • Changes made during Open Enrollment take effect on January 1, so you must act before December 7 to switch for the new year.
  • may have access to life events — such as moving, losing employer coverage, or getting married — open a 60-day Special Enrollment Period outside the annual window.
  • If you miss both Open Enrollment and any Special Enrollment Period you may have access to for, you cannot switch plans until the following October.
  • You must contact your new plan or Medicare directly to switch; your current plan cannot prevent you from leaving during an open period.

Open Enrollment: The annual window for all Medicare beneficiaries

Open Enrollment is the one time every year when anyone on Medicare can switch plans without needing a reason. It runs from October 15 to December 7. During these seven weeks, you can move between Medicare Advantage plans, switch from Medicare Advantage back to Original Medicare, change your prescription drug plan (Part D), or add a Medigap supplemental policy if you are on Original Medicare.

The important date is firm: December 7 at 11:59 p.m. Eastern time. If you call or submit a request after that date, it will not be processed for a January 1 start date. You can switch by calling your new plan directly, calling Medicare at 1-800-MEDICARE, or using Medicare.gov. Write down your confirmation number when you switch — you will need it to verify the change took effect.

Your new coverage begins January 1. Your old plan ends December 31. During the overlap in late December, you may receive bills or notices from both plans; this is normal. Make sure you have your new plan's member ID card before January 1 so you can use it at the pharmacy or doctor's office.

Special Enrollment Periods: When you can switch outside of October and November

A may have access to life event opens a Special Enrollment Period, usually lasting 60 days from the date the event happens. Common may have access to events include moving to a new state or county, losing employer-sponsored health coverage, getting married or divorced, having a baby or adopting a child, becoming a U.S. citizen, or being released from prison. If you experience one of these events, you can switch plans even if it is January, June, or any other month outside Open Enrollment.

The timing matters. Your Special Enrollment Period typically starts the month your event happens. For example, if you move on March 15, your 60-day window usually opens March 1. You must request the switch within that 60-day window. If you wait until day 61, the window closes and you cannot switch until the next Open Enrollment in October.

To use a Special Enrollment Period, you will need to prove the may have access to event. Have documents ready: a lease or utility bill for a move, a termination letter from your employer for job loss, a marriage certificate, a birth certificate, or a naturalization certificate. Call Medicare at 1-800-MEDICARE or contact your new plan directly and tell them about your life event. They will ask for proof before processing your switch.

What happens if you miss the important date

If you do not switch during Open Enrollment and you do not have a may have access to life event, you are locked into your current plan for the entire year. You cannot switch in January, February, or any month until October 15 arrives again. This applies even if your plan's premiums go up, your doctor leaves the network, or your prescription drug coverage changes.

The only exception is if you later experience a may have access to life event. For instance, if you miss Open Enrollment in December but move to a new state in March, that move opens a Special Enrollment Period and you can switch then. But if no may have access to event happens, you must wait until October.

This is why it is important to review your plan each September or early October, before Open Enrollment starts. Check whether your doctors are still in-network, whether your medications are still covered, and whether the premium and out-of-pocket costs still fit your budget. If something has changed for the worse, you have time to switch during Open Enrollment.

How to switch plans during an open period

You have three main ways to switch: call your new plan directly, call Medicare, or use Medicare.gov. If you know which plan you want to join, calling the plan is often fastest — they can answer questions about coverage and costs specific to your situation, and they can process your switch on the spot. Ask for a confirmation number and write it down.

If you are not sure which plan is best for you, call Medicare at 1-800-MEDICARE. Representatives can walk you through your options, show you plans available in your area, and help you compare costs. They can also process your switch. This call is free and available seven days a week.

On Medicare.gov, you can use the Plan Finder tool to search plans by your zip code, see which doctors and pharmacies are in-network, and check drug coverage. Once you have chosen a plan, you can switch directly through the website. Keep your confirmation number.

Do not wait until December 6 or 7. If the system is busy or there is a problem, you may not be able to complete your switch in time. Aim to switch by early December at the latest.

Switching from Medicare Advantage back to Original Medicare

If you are on a Medicare Advantage plan and want to return to Original Medicare, you can do so during Open Enrollment. This is called disenrolling from Medicare Advantage. You do not need a reason — you can straightforward decide that Original Medicare is a better fit.

When you disenroll, you lose your Medicare Advantage coverage on December 31. Original Medicare (Part A and Part B) automatically resumes on January 1. However, you should also sign up for a Part D prescription drug plan and consider a Medigap supplemental policy at the same time, because Original Medicare does not cover prescriptions or gaps in coverage.

If you are switching back to Original Medicare and want a Medigap policy, you have a special right: you can buy a Medigap plan without medical underwriting during your first six months back on Original Medicare. This means the insurance company cannot deny you or charge you more based on your health history. This window is valuable — if you wait past six months, you may face higher premiums or denial. Contact a Medigap insurer as soon as your Original Medicare coverage begins.

Switching prescription drug plans only

You do not have to switch your entire Medicare Advantage or Original Medicare plan if you only want to change your prescription drug coverage. During Open Enrollment, you can drop your current Part D plan and join a different one, or add Part D if you do not currently have it. This is called a Part D-only switch.

Part D plans change their drug formularies (the list of covered medications) and their costs every year. If your medication is no longer covered, or if the copay has gone up significantly, switching plans during Open Enrollment can lower your costs. Use the Plan Finder on Medicare.gov to see which Part D plans cover your specific medications and compare the total yearly cost.

If you are on Original Medicare and want to add or switch Part D, you can do this during Open Enrollment. If you are on Medicare Advantage, your plan's drug coverage is included, so you cannot switch to a different Part D plan — but you can switch to a different Medicare Advantage plan that offers better drug coverage.

Frequently Asked Questions

Can I switch plans more than once during Open Enrollment?

Yes. If you change your mind, you can switch again before December 7. However, only your final switch will take effect on January 1. If you switch to Plan A on November 1 and then switch to Plan B on November 20, you will be enrolled in Plan B on January 1, not Plan A. Keep track of your most recent confirmation number.

What if my doctor leaves my plan's network after I switch?

If your new plan's network changes after January 1 and your doctor leaves, you cannot switch plans until the next Open Enrollment — unless you may have access to for a Special Enrollment Period. This is why it is important to check the plan's current network before you switch, not just assume it will stay the same.

Do I have to notify my old plan that I am leaving?

No. When you enroll in a new plan, Medicare automatically disenrolls you from your old one on December 31. You do not need to call your old plan. However, you may receive final bills or notices from them in late December; these are routine and do not mean your switch did not go through.

Can I switch plans if I am in the middle of treatment?

Yes. You can switch plans at any time during an open enrollment period, even if you are receiving ongoing medical care. However, your new plan may have different out-of-pocket costs and different in-network providers. Before you switch, confirm that your doctor and any specialists you see are in your new plan's network.

What if I miss the December 7 important date by one day?

Your switch will not be processed for January 1. You will remain in your current plan for the entire year unless you later experience a may have access to life event that opens a Special Enrollment Period. This is why setting a reminder in early December is important — do not wait until the last week.