Medicare Advantage open enrollment runs from January 1 to March 31 each year

During this three-month window, you can switch from one Medicare Advantage plan to another, drop Medicare Advantage and return to Original Medicare, or join Medicare Advantage if you are currently on Original Medicare. This is the main period when changes take effect on the first day of the following month. Outside this window, you can only make changes if you experience a may have access to life event — such as moving to a new county, losing employer coverage, or becoming newly may be able to access for Medicare.

The exact dates are set by the federal government and do not change year to year. January 1 through March 31 is the standard window. Any changes you make during this period will be active starting April 1. If you miss the important date, you will be locked into your current plan for the rest of the year unless a may have access to event occurs.

Key Takeaways

  • Open enrollment for Medicare Advantage runs January 1 to March 31 each year, and changes take effect April 1.
  • You can switch between Medicare Advantage plans, drop to Original Medicare, or join Medicare Advantage for the first time during this window.
  • If you miss the important date, you cannot change plans until the next open enrollment period unless you have a may have access to life event such as moving or losing coverage.
  • Your current plan automatically renews on January 1 if you do not make a change, so inaction means staying with what you have.
  • You can compare plans and make changes online through Medicare.gov, by phone, or by mail — the method does not affect your important date.

What counts as a may have access to life event outside open enrollment

If you experience certain changes in your circumstances, you can make plan changes outside the January 1 to March 31 window. These are called may have access to events, and they give you a limited window — usually 60 days from the date of the event — to switch plans. Common may have access to events include moving to a different county or state, losing employer or union coverage, becoming newly may be able to access for Medicare, or having a change in your Medicaid status.

Death of a spouse, divorce, and loss of coverage through a family member also count. If you believe you have had a may have access to event, contact Medicare at 1-800-MEDICARE to report it and confirm whether it opens a special enrollment period for you. Do not wait — the 60-day window is firm, and missing it means you cannot change until the next January 1.

How to make changes during open enrollment

You have three main routes: online through Medicare.gov, by phone at 1-800-MEDICARE, or by mail. The online method is fastest — you can log into your Medicare account, review plans side by side, and submit your choice in minutes. The website shows you plans available in your zip code, their premiums, deductibles, and which doctors and pharmacies are in-network.

If you call, a Medicare representative will walk you through available plans and help you enroll over the phone. If you prefer mail, you can request a paper enrollment form from Medicare and return it by the March 31 important date. Whichever method you use, your change takes effect April 1, so you will have a new plan ID card and new coverage rules starting that date.

What happens if you do nothing during open enrollment

Your current Medicare Advantage plan automatically continues into the next year. You will stay with the same plan, the same premium, and the same coverage rules unless you actively choose to change. This is called auto-renewal, and it happens on January 1 whether you take action or not.

However, plans can change their premiums, deductibles, and networks from year to year. Even if you do nothing, your plan may cost more or cover different doctors in the coming year. For this reason, it is worth reviewing your current plan each January to see whether it still fits your needs and budget, even if you decide to keep it.

Important dates and important date to mark

January 1 is when open enrollment begins and when your current plan auto-renews if you make no change. March 31 is the final day to submit a change — any request received after midnight on March 31 will be rejected. April 1 is when any changes you made take effect. If you are making a change, submit it well before March 31 to avoid last-minute problems.

If you have a may have access to life event, you typically have 60 days from the date of that event to make a change. For example, if you move on June 15, you have until August 14 to switch plans. Mark the 60-day important date in your calendar and contact Medicare before that date expires.

How plan changes affect your coverage mid-year

If you switch Medicare Advantage plans during open enrollment, your old plan ends on March 31 and your new plan begins on April 1. There is no gap in coverage. However, any deductible you have already met in your old plan does not carry over to your new plan — you start fresh with a new deductible on April 1. The same applies to out-of-pocket maximums and any prior authorization approvals your doctor may have obtained.

If you are in the middle of a course of treatment, check whether your new plan covers the same doctors and medications before you switch. Some plans have different networks and formularies — the list of covered drugs — so a medication your old plan covered might not be on your new plan's list, or your doctor might not be in-network.

Special rules if you are turning 65 or newly may be able to access

When you first become may be able to access for Medicare at age 65 or due to disability or end-stage renal disease, you have an initial enrollment period that is different from the standard open enrollment window. Your initial enrollment period is seven months long: three months before the month you turn 65, the month itself, and three months after. During this window, you can enroll in Medicare Advantage without waiting for January 1.

If you miss your initial enrollment period, you may face a late enrollment penalty that increases your premium permanently. Once your initial enrollment period ends, you are locked into the plan you chose until the next January 1 open enrollment, unless you have a may have access to life event.

Frequently Asked Questions

Can I switch Medicare Advantage plans in December?

No. Open enrollment does not begin until January 1. If you try to make a change in December, it will not be processed. Plan ahead and make your change during January, February, or early March to may support it takes effect on April 1.

What if I move to a different state during the year?

Moving to a different state or county is a may have access to life event. You have 60 days from your move date to switch plans. Contact Medicare at 1-800-MEDICARE and report your move so they can open a special enrollment period for you. Your new plan can start as soon as the first of the month following your request.

Do I lose my doctor if I switch plans?

Not necessarily, but you need to check. Before you switch, look up your current doctor in the new plan's network on Medicare.gov or call the new plan directly. If your doctor is not in-network, you may have to pay more or switch doctors. Some plans have different networks, so this is a critical step before you enroll.

Can I go back to Original Medicare during open enrollment?

Yes. During January 1 to March 31, you can drop your Medicare Advantage plan and return to Original Medicare. Your Original Medicare coverage begins April 1. If you do this, you may also want to enroll in a Medigap or Part D plan at the same time, since Original Medicare does not include prescription drug coverage.

What happens if I miss the March 31 important date?

Your current plan continues automatically into the next year. You cannot change plans until January 1 of the following year, unless you experience a may have access to life event such as moving, losing coverage, or a change in your Medicaid status. If a may have access to event occurs, contact Medicare within 60 days to report it.