The Medicare Annual Enrollment Period (AEP): What You Need to Know Before October 15
Medicare coverage doesn't necessarily stay the same from one year to the next. Premiums, deductibles, provider networks, prescription drug coverage, covered benefits, and other plan details can change for the upcoming year.
For Medicare beneficiaries, the Annual Enrollment Period (AEP), also commonly called Medicare Open Enrollment, is an important opportunity to review current coverage and decide whether changes may be appropriate.
The AEP runs from October 15 through December 7 every year. Changes made during this period generally take effect on January 1 of the following year.
For 2026, this means Medicare beneficiaries have from October 15 through December 7, 2026, to make eligible changes to coverage for 2027.
The AEP doesn't mean you have to change your Medicare coverage. If your current plan continues to meet your healthcare and prescription needs, you can generally keep it. However, reviewing your coverage before making that decision is important because your plan's costs and benefits may change.
This guide explains what the AEP is, who can use it, what changes are allowed, and what you should review before October 15.
What Is the Medicare Annual Enrollment Period?
The Medicare Annual Enrollment Period is the yearly period when people with Medicare can make certain changes to their Medicare health and prescription drug coverage.
Medicare officially refers to this period as Open Enrollment, and it takes place from October 15 through December 7. Any changes made during the period generally become effective January 1 of the following year.
During this period, eligible beneficiaries can make changes involving Medicare Advantage and Medicare prescription drug coverage. They can also switch between Original Medicare and Medicare Advantage.
The AEP is especially important because Medicare Advantage and Part D plans can change their premiums, deductibles, formularies, provider networks, and covered benefits for the upcoming year.
The key point is that your current plan may not look exactly the same next year.
That is why Medicare recommends reviewing your coverage each year, even if you have been satisfied with your plan.
When Is the Medicare AEP in 2026?
The Medicare Annual Enrollment Period for 2026 is:
October 15, 2026 – December 7, 2026
Changes made during this period generally become effective January 1, 2027, as long as the plan receives the enrollment request by December 7.
The timing is important because waiting until the final days of AEP can leave less time to compare plans, confirm provider participation, review prescription coverage, and complete enrollment.
Medicare's official guidance encourages beneficiaries to begin preparing before October 15. Around October 1, people can start reviewing notices from their current plans and previewing plan options for the upcoming year.
Starting early can make the process less stressful and give you time to ask questions before making a decision.
Who Can Use the Medicare Annual Enrollment Period?
The AEP is generally available to people who already have Medicare and want to make eligible changes to their Medicare health or prescription drug coverage.
This includes people currently enrolled in Medicare Advantage and people with Original Medicare who have Medicare Part D prescription drug coverage.
During Open Enrollment, Medicare beneficiaries can:
- Join, switch, or drop a Medicare Advantage plan.
- Join, switch, or drop a Medicare Part D prescription drug plan if they have Original Medicare.
- Switch from Original Medicare to Medicare Advantage.
- Switch from Medicare Advantage back to Original Medicare.
- Add or drop Medicare prescription drug coverage when applicable.
However, the AEP is not the same as the Initial Enrollment Period for people becoming eligible for Medicare for the first time.
If you're approaching Medicare eligibility, you should learn about your Initial Enrollment Period and other enrollment opportunities rather than waiting for the October AEP.
Similarly, some people may qualify for a Special Enrollment Period (SEP) because of specific life circumstances. These enrollment opportunities have different rules and deadlines.
What Can You Change During AEP?
One of the most important things to understand about AEP is that it provides several options rather than requiring everyone to make the same type of change.
Switching Medicare Advantage Plans
If you're currently enrolled in Medicare Advantage, you can generally switch to another Medicare Advantage plan during Open Enrollment.
You may choose a plan with or without prescription drug coverage, depending on your circumstances.
This can be useful if your current plan's network, premiums, benefits, prescription coverage, or other features no longer fit your needs.
However, choosing a new plan should involve more than comparing monthly premiums.
You should also consider whether your doctors participate in the network, whether your prescriptions are covered, and whether the plan's costs and benefits work for your expected healthcare needs.
Changing Part D Drug Plans
If you have Original Medicare and a standalone Part D prescription drug plan, you can generally switch to another Part D plan during AEP.
This is particularly important because prescription drug plans can change their formularies, premiums, deductibles, pharmacy networks, and cost-sharing requirements.
A medication covered at a preferred cost this year may have different coverage rules next year.
That makes reviewing your prescription list one of the most important parts of your annual Medicare review.
Switching Between Original Medicare and Medicare Advantage
The AEP also allows eligible beneficiaries to change how they receive Medicare coverage.
You can generally switch from Original Medicare to Medicare Advantage or from Medicare Advantage back to Original Medicare during Open Enrollment.
If you move to Original Medicare, you may also need to consider whether you want a separate Part D prescription drug plan and whether you qualify for or want Medicare Supplement Insurance, commonly called Medigap.
Medicare notes that Medigap has its own enrollment rules and guaranteed-issue rights, so beneficiaries should not assume that switching to Original Medicare automatically guarantees the ability to purchase any Medigap policy at the same terms.
This is one reason why changing coverage should be considered carefully before submitting an enrollment request.
Do You Have to Change Your Medicare Plan?
No.
AEP is an opportunity to make eligible changes, not a requirement to switch plans.
If you review your current coverage and determine that it continues to meet your healthcare and prescription needs, you can generally keep it.
Medicare's guidance specifically notes that if someone chooses to keep their current Medicare health and drug coverage, they generally don't need to take action simply because AEP arrives. Their coverage will continue, although the plan's new-year costs and benefits may still change.
However, "keeping the same plan" should ideally be an informed decision.
Your current plan may have updated its premium, deductible, provider network, prescription formulary, or supplemental benefits for the upcoming year.
Reviewing the changes before deciding to stay can help you avoid being surprised in January.
What Is the Annual Notice of Change?
One of the most important documents to review before AEP is your plan's Annual Notice of Change (ANOC).
Medicare Advantage and Part D plan members generally receive an Annual Notice of Change before the Open Enrollment Period. The document explains changes that will apply to the plan for the upcoming year.
Changes can affect premiums, deductibles, benefits, cost-sharing, coverage rules, prescription coverage, and other aspects of the plan.
Rather than filing the document away, read it alongside your current healthcare needs.
For example, if your plan's premium is staying relatively stable but your prescription costs are changing significantly, that could be more important to you than the premium itself.
Similarly, a change in your preferred doctor's network could matter more than a small change in the monthly premium.
What Should You Review Before October 15?
Preparing before AEP begins can make the decision-making process much easier.
Your Doctors and Healthcare Providers
Make a list of the doctors, specialists, hospitals, and other healthcare providers you regularly use.
If you're considering a Medicare Advantage plan, verify that the providers you want to continue seeing participate in the plan's network.
Don't rely solely on an old provider directory. Confirm current information through Medicare's plan comparison tools and, when necessary, directly with the provider and plan.
Your Prescription Medications
Create an updated list of every prescription medication you take.
When reviewing Part D or Medicare Advantage drug coverage, check whether each medication is included in the plan's formulary and determine the applicable cost-sharing requirements.
Also check whether your preferred pharmacy participates in the plan's network and whether there are restrictions such as quantity limits, prior authorization, or step therapy.
Your Healthcare Spending
Review what you actually spent on healthcare during the current year.
Look at premiums, copayments, coinsurance, deductibles, prescription costs, and other significant healthcare expenses.
Then consider whether you expect your healthcare needs to change next year.
A plan that worked well when you rarely visited a doctor may not be the best fit if you anticipate surgery, frequent specialist visits, or ongoing treatment.
Your Plan's Benefits
Medicare Advantage plans may offer additional benefits beyond Original Medicare, depending on the plan.
Review which benefits you actually use rather than focusing only on the number of benefits advertised.
Consider whether dental, vision, hearing, fitness, transportation, or other supplemental benefits are meaningful to your healthcare needs.
Why 2027 Medicare Changes Make This Year's Review Important
The 2026 AEP is particularly relevant because beneficiaries are choosing coverage for 2027, and CMS has already finalized several policy changes affecting Medicare Advantage and Part D.
For example, CMS's 2027 Medicare Advantage and Part D final rule includes changes to Part D, including codification of Inflation Reduction Act provisions affecting the benefit structure. CMS also finalized updates involving Star Ratings and certain enrollment processes.
CMS also released preliminary 2027 Part D bid information on July 28, 2026, as plan sponsors prepare their offerings for Medicare Open Enrollment.
This does not mean every beneficiary will experience the same changes or that a particular plan will necessarily become more or less expensive.
It does mean that reviewing your specific plan for 2027 is important rather than assuming your 2026 coverage will remain unchanged.
Don't Focus Only on the Monthly Premium
A low monthly premium can be attractive, but it is only one part of your Medicare coverage.
When reviewing a plan, consider how the premium works alongside deductibles, copayments, coinsurance, prescription costs, provider networks, and annual out-of-pocket limits.
For someone who takes several medications or frequently visits specialists, a plan with a slightly higher premium could potentially have lower overall costs depending on the plan's benefits and healthcare usage.
Likewise, a plan with attractive supplemental benefits may not be the right choice if your preferred providers are outside the network.
The goal during AEP should be to find coverage that fits your overall healthcare needs, not simply the lowest advertised monthly premium.
Use Medicare's Official Plan Comparison Tools
Medicare provides official resources to help beneficiaries compare available health and drug plans.
The Medicare Plan Compare tool can help you review plans available in your area and examine coverage information.
Medicare also advises beneficiaries to use official sources such as Medicare.gov, the Medicare & You handbook, and 1-800-MEDICARE when looking for unbiased Medicare information.
If you receive marketing materials from insurance companies or other organizations during AEP, remember that advertisements may highlight specific benefits without showing the complete picture of a plan.
Review the plan's full details before making a decision.
What Happens After You Make a Change?
If you make an eligible change during AEP, the new coverage generally begins January 1 of the following year.
For the 2026 AEP, this means a change made during October 15 through December 7 will generally take effect January 1, 2027.
After enrolling in a new plan, review the confirmation materials you receive.
Before January 1, make sure you understand how to access your new member ID card, provider directory, pharmacy information, and other plan resources.
If you're switching plans, don't assume every part of your healthcare experience will transfer automatically. Confirm prescriptions, providers, appointments, and other important services before the new coverage begins.
What If You Miss the December 7 Deadline?
The December 7 deadline is important because AEP ends on that date.
However, Medicare has other enrollment periods and Special Enrollment Periods that may apply depending on your circumstances.
For example, Medicare Advantage has a separate Medicare Advantage Open Enrollment Period from January 1 through March 31. During that period, people already enrolled in Medicare Advantage can generally make one change, such as switching to another Medicare Advantage plan or returning to Original Medicare.
These periods have different rules from AEP, so don't assume that an opportunity available during one enrollment period is available during another.
If you're unsure which enrollment period applies to you, consult Medicare directly or speak with a qualified Medicare professional.
A Simple Way to Prepare Before October 15
You don't need to wait until October 15 to begin preparing.
Start by gathering your current plan documents, including your Annual Notice of Change when it arrives.
Then make a list of your doctors, medications, pharmacies, and important healthcare services.
Review what you spent on healthcare this year and consider whether your needs are likely to change in 2027.
Once 2027 plan information becomes available, compare your current coverage with other options and pay particular attention to the areas that matter most to you.
Finally, give yourself enough time to make a decision before December 7.
A thoughtful Medicare review is much easier when you're not trying to make a decision at the last minute.
Conclusion
The Medicare Annual Enrollment Period is an important opportunity to review your coverage before the new year.
From October 15 through December 7, 2026, Medicare beneficiaries can make eligible changes to Medicare Advantage and Part D coverage, including switching plans or changing between Original Medicare and Medicare Advantage. Changes generally take effect January 1, 2027.
But AEP isn't simply about choosing a new plan. It's about determining whether your current coverage still fits your healthcare needs.
Review your providers, prescriptions, costs, benefits, and plan changes before making a decision. Use your Annual Notice of Change and Medicare's official comparison tools, and don't assume that the plan you've had this year will have exactly the same costs and benefits next year.
The best Medicare decision is an informed one. Starting your review before October 15 can give you the time you need to understand your options and enter 2027 with greater confidence.
Prepare for Medicare AEP With Confidence
Medicare decisions can feel complicated, especially when plan costs, prescription coverage, provider networks, and benefits change from year to year. If you have questions about Medicare Advantage, Original Medicare, Part D, or your coverage options, schedule a consultation.
For more educational information about Medicare and health insurance, visit Belle Vida Insurance.