Medicare Advantage open enrollment runs from January 1 to March 31 each year
During this three-month window, you can switch to a different Medicare Advantage plan, switch back to Original Medicare, or make changes to your prescription drug coverage. This is different from the general Medicare enrollment period in the fall — open enrollment is specifically for people already on Medicare who want to change plans.
You do not need to wait for a special circumstance to make a change during open enrollment. If you are unhappy with your current plan's costs, doctors, or coverage, you can switch without penalty. The new plan takes effect on January 1 of the following year, even if you switch on March 31.
Open enrollment happens every year at the same time. Mark January 1 on your calendar now so you do not miss the important date — if you want to change plans for the next year, you must act by March 31.
Key Takeaways
- Open enrollment for Medicare Advantage runs January 1 to March 31 each year, and any change you make takes effect January 1 of the next year.
- You can switch to a different Medicare Advantage plan, return to Original Medicare, or change your prescription drug plan during this window without a penalty.
- You do not need a may have access to life event (like moving or losing coverage) to make a change during open enrollment — anyone on Medicare can switch.
- After March 31, you are locked into your plan for the rest of the year unless you experience a may have access to event such as moving, losing employer coverage, or a major life change.
What counts as a may have access to event if you miss open enrollment
If you do not make a change during the January to March window, you normally cannot switch plans until the next open enrollment period. However, certain life events let you change plans outside of open enrollment.
A may have access to event includes moving to a new state or county, losing employer or union coverage, becoming may be able to access for Medicaid, getting married or divorced, or having a significant change in your health status. Death of a spouse also qualifies. When a may have access to event happens, you usually have 60 days from the date of the event to make a change.
Contact Medicare at 1-800-MEDICARE to report a may have access to event and ask whether you can switch plans. Have your Medicare card and the date of the event ready when you call. Medicare will tell you whether your situation qualifies and how long you have to make a change.
How to switch plans during open enrollment
You have three main ways to switch: online through Medicare.gov, by phone with Medicare, or in person with help from a counselor.
The online route is fastest. Go to Medicare.gov, sign in with your username and password, and look for the option to make changes to your coverage. You can compare plans side by side, see which doctors and pharmacies are in each network, and check prescription drug costs. Once you choose a new plan, submit your selection before midnight on March 31.
If you prefer to talk to someone, call 1-800-MEDICARE (1-800-633-4227). Representatives are available seven days a week, and they can walk you through your options and help you switch. This call is free.
You can also get free, in-person help from a State Health Insurance information Program (SHIP) counselor. SHIP counselors work in every state and can review your current plan, explain your options, and help you switch. To find your state's SHIP, search "SHIP" plus your state name online, or call 1-800-MEDICARE and ask for the number.
What happens to your current coverage when you switch
Your old Medicare Advantage plan ends on December 31, and your new plan starts on January 1. There is no gap in coverage if you switch during open enrollment — the transition is automatic.
Before January 1 arrives, your new plan will send you an insurance card and information about how to use your coverage. Read the welcome packet carefully, because each plan has different rules about which doctors you can see, which hospitals are in-network, and how much you pay for prescriptions.
If you switch back to Original Medicare during open enrollment, you may want to buy a Medigap or Medicaid policy to cover costs that Original Medicare does not pay. You have a special window to buy Medigap without medical underwriting when you switch from Medicare Advantage, but that window is limited — usually 63 days from the date your Medicare Advantage plan ends. Do not wait until after January 1 to look into Medigap, because you may lose this protection.
Why you might want to switch plans
Medicare Advantage plans change their costs, covered drugs, and doctor networks every year. A plan that worked well for you in 2024 might cost more or cover fewer of your doctors in 2025.
Common reasons to switch include a change in your out-of-pocket costs (copays, coinsurance, or deductibles), a doctor or specialist leaving your plan's network, a prescription drug you take no longer being covered, or a move to a new state where your current plan does not operate. Some people switch because they want to try a plan with different benefits, such as dental or vision coverage.
Review your plan's annual notice of change, which Medicare mails to you in September or October each year. This document lists what is changing for the next year. If you see changes that affect you, open enrollment is your chance to switch.
What to do before open enrollment ends
Start by gathering information about your current plan and your options. Pull out your Medicare Advantage plan documents and note your current costs and which doctors you see. Then use Medicare.gov's plan comparison tool to look at other plans available in your area.
Make a list of the doctors and specialists you see regularly, and check whether they are in-network for any new plan you are considering. Call the plan's customer service number if the website does not have a clear answer — in-network status can change, and you want current information.
If you take prescription drugs, use the plan's formulary (the list of covered drugs) to check whether your medications are covered and at what cost. Some plans require prior authorization before they will cover certain drugs, which means your doctor has to get approval first.
Once you have compared plans and made your choice, switch before March 31. Do not assume you can switch on April 1 — the important date is firm, and missing it means you are locked in for the rest of the year.
Frequently Asked Questions
Can I switch Medicare Advantage plans more than once during open enrollment?
Yes. You can switch plans as many times as you want between January 1 and March 31. Each time you switch, your previous choice is cancelled and your new choice takes effect on January 1. Only your final selection counts, so make sure you are happy with your last choice before March 31 ends.
What if my doctor leaves my plan's network after I switch?
If your doctor leaves the network after you switch but before the plan year ends, contact your new plan's customer service. Many plans allow you to continue seeing an out-of-network doctor for a limited time or may let you switch plans outside of open enrollment if the change is significant enough. Ask what your options are.
Do I lose coverage if I switch on March 31?
No. Your old plan covers you through December 31, and your new plan starts on January 1. There is no gap. Your new plan will mail your insurance card and welcome materials before the year changes.
Can I switch from Medicare Advantage to Original Medicare during open enrollment?
Yes. You can drop Medicare Advantage and go back to Original Medicare anytime during open enrollment. If you do, consider buying a Medigap policy within 63 days, because you have special protections during this window that you may not have later.
What if I do not receive my plan's annual notice of change?
Call your current plan's customer service number and ask them to mail it to you, or visit the plan's website to read it. You can also call 1-800-MEDICARE and ask them to send you information about what is changing in your plan for the next year.