Medicare Annual Enrollment Period (AEP) 2026: Dates, Rules, and What You Can Change
Learn when the Medicare Annual Enrollment Period runs, what changes you can make to your coverage, and tips for comparing plans during AEP.
The Medicare Annual Enrollment Period is one of the most important times of the year for Medicare beneficiaries. This is your opportunity to review and change your Medicare coverage for the following year.
This article explains when the Annual Enrollment Period occurs, what changes you can and cannot make, and how to make the most of this enrollment window.
What Is the Annual Enrollment Period?
The Medicare Annual Enrollment Period, also called AEP or Fall Open Enrollment, is a seven-week period each year. During this time, anyone with Medicare can make changes to their coverage.
The Annual Enrollment Period runs from October 15 through December 7 every year. Any changes you make during this period take effect on January 1 of the following year.
2026 Annual Enrollment Period Dates
For 2026 coverage, the Annual Enrollment Period runs from October 15, 2025 through December 7, 2025.
Coverage changes made during this window take effect on January 1, 2026. These dates are the same every year and do not change.
What You CAN Change During AEP
During the Annual Enrollment Period, you can make several types of changes to your Medicare coverage:
Switch from Original Medicare to Medicare Advantage
If you have Original Medicare, you can enroll in a Medicare Advantage plan. This replaces your Original Medicare coverage.
Switch from Medicare Advantage to Original Medicare
If you have a Medicare Advantage plan, you can disenroll and return to Original Medicare. You can also add a Part D prescription drug plan when you do this.
Switch from One Medicare Advantage Plan to Another
You can change from your current Medicare Advantage plan to a different Medicare Advantage plan. This could be from a different company or a different plan type from the same company.
Join a Medicare Part D Prescription Drug Plan
If you have Original Medicare without drug coverage, you can add a standalone Part D plan. This is important even if you do not take many medications currently.
Switch from One Part D Plan to Another
You can change from your current Part D plan to a different one. This is useful if your medications have changed or if your plan has increased costs.
Drop Your Part D Coverage
You can drop your Part D coverage entirely. However, this is generally not recommended unless you have creditable prescription coverage from another source. If you go without coverage, you may face a late enrollment penalty when you enroll later.
What You CANNOT Change During AEP
The Annual Enrollment Period does not apply to all types of Medicare coverage. Here is what you cannot change during AEP:
Medicare Supplement (Medigap) Plans
AEP does not provide special rights to enroll in or change Medicare Supplement plans. You can apply for a Medigap plan at any time during the year, but you may need to answer health questions.
The best time to get a Medigap plan is during your Medigap Open Enrollment Period, which occurs when you first enroll in Medicare Part B at age 65 or older.
Original Medicare Parts A and B
You cannot drop your Medicare Part A or Part B coverage during AEP. Once you have these, they remain in effect unless you take specific actions to disenroll, which is rarely advisable.
Why the Annual Enrollment Period Matters
Even if you are happy with your current coverage, you should review your options during AEP. Plans can change from year to year. Your plan may have:
- Increased premiums or other costs
- Changed which drugs are covered or what they cost
- Removed doctors or hospitals from the network
- Changed covered benefits or services
Your own healthcare needs may have changed as well. You may be taking new medications or seeing different doctors. Reviewing your coverage ensures you still have the right plan.
How to Compare Plans During AEP
Review Your Current Plan
Before the Annual Enrollment Period begins, you should receive an Annual Notice of Change from your current plan. This document explains how your plan will change for the next year.
Review this notice carefully. Pay attention to changes in premiums, deductibles, copays, covered drugs, and provider networks.
List Your Medications
Make a list of all the prescription medications you take, including dosages. When comparing Part D plans or Medicare Advantage plans with drug coverage, enter your medications into the Medicare Plan Finder to see which plans cover your drugs at the lowest cost.
Check Provider Networks
If you are considering a Medicare Advantage plan, verify that your doctors and hospitals are in the plan network. Networks can change from year to year. Just because your doctor is in the network this year does not guarantee they will be next year.
Compare Total Costs
Do not just look at monthly premiums. Consider total annual costs, including premiums, deductibles, copays, and coinsurance. A plan with a low premium may have high costs when you use healthcare services.
Use the Medicare Plan Finder
The Medicare Plan Finder tool on Medicare.gov is the best resource for comparing plans. You can enter your zip code, medications, and doctors to see personalized plan recommendations and cost estimates.
The tool is updated every year with current plan information. It is free to use and provides unbiased comparisons.
How to Make Changes During AEP
You have several options for enrolling in or changing plans during the Annual Enrollment Period:
Online
You can enroll in plans through Medicare.gov or directly through the insurance company website. This is often the fastest method.
By Phone
You can call Medicare at 1-800-MEDICARE or call the insurance company directly. Representatives can answer questions and help you enroll over the phone.
By Mail
You can request a paper enrollment form and mail it to the insurance company. Make sure to mail it early enough that it arrives before the December 7 deadline.
Through an Agent or Broker
You can work with a licensed insurance agent who specializes in Medicare. Agents can explain your options, compare plans, and help you enroll. Their services are typically free to you.
What Happens After You Enroll
After you enroll in a new plan or make changes during AEP, you will receive confirmation from the insurance company. Your new coverage begins on January 1.
If you switch plans, your old plan will automatically end on December 31. You do not need to disenroll from your old plan separately.
You should receive your new plan materials, including your membership card, before January 1. If you do not receive these by late December, contact the insurance company.
Other Enrollment Periods to Know About
Medicare Advantage Open Enrollment Period
If you are already enrolled in a Medicare Advantage plan, you get another chance to make changes from January 1 through March 31. During this period, you can switch to a different Medicare Advantage plan or return to Original Medicare and add a Part D plan.
Special Enrollment Periods
If you miss the Annual Enrollment Period, you may still be able to make changes if you qualify for a Special Enrollment Period. Qualifying events include moving, losing other coverage, or qualifying for Extra Help with drug costs.
Common Mistakes to Avoid During AEP
Not Reviewing Your Current Plan
Many people assume their plan stays the same each year. However, plans often change costs, coverage, and networks. Always review your Annual Notice of Change.
Focusing Only on Premium
A plan with a low or zero premium may have high costs when you need care. Look at total annual costs, including deductibles, copays, and drug costs.
Not Checking Drug Coverage
Drug formularies change every year. A drug that was covered this year may not be covered next year, or it may move to a higher cost tier. Always check that your medications are covered.
Waiting Until the Last Minute
Do not wait until December to review your options. Plans can sell out or stop accepting new members. Start your research in October to give yourself plenty of time to compare and make an informed decision.
Tips for a Successful Annual Enrollment Period
- Start reviewing your options as soon as AEP begins on October 15
- Gather information about your current medications, doctors, and expected healthcare needs
- Use the Medicare Plan Finder tool to compare your options objectively
- Consider working with a licensed Medicare agent for personalized help
- Ask questions before enrolling to make sure you understand the plan
- Keep confirmation of your enrollment for your records
Final Thoughts
The Medicare Annual Enrollment Period is your opportunity to review and adjust your coverage. Even if you are satisfied with your current plan, it is important to check for changes that may affect you next year.
Take advantage of this window from October 15 to December 7 to compare your options. A little time spent during AEP can save you money and ensure you have the right coverage for your healthcare needs.
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Frequently Asked Questions
When is the Medicare Annual Enrollment Period?
The Medicare Annual Enrollment Period runs from October 15 through December 7 every year. Changes you make during this time take effect on January 1 of the following year.
Can I switch from Medicare Advantage to Original Medicare during AEP?
Yes. During the Annual Enrollment Period, you can leave your Medicare Advantage plan and return to Original Medicare. You can also add a Part D prescription drug plan at the same time.
Can I change my Medicare Supplement plan during AEP?
The Annual Enrollment Period does not apply to Medicare Supplement plans. You can change Medigap plans at any time, but you may need to answer health questions unless you have a guaranteed issue right.
What happens if I miss the Annual Enrollment Period?
If you miss AEP, you generally have to wait until the next year to make changes unless you qualify for a Special Enrollment Period. There is also a Medicare Advantage Open Enrollment Period from January 1 to March 31 for people already in Medicare Advantage.
Can I enroll in Medicare for the first time during AEP?
AEP is for people already enrolled in Medicare. If you are turning 65 or becoming eligible for Medicare, you should enroll during your Initial Enrollment Period, which is different from AEP.
Do I need to do anything during AEP if I am happy with my current plan?
You should still review your plan during AEP. Even if you are satisfied, your plan may have changed its costs, coverage, or network for the next year. Comparing options ensures you still have the right coverage.
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