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Insight · Medicare
Medicare Open Enrollment 2026: Review Your Plan Before Dec 7
Every fall, Medicare gives you a window to reconsider your coverage - and most people skip it entirely. That could be a costly habit. Even if you were happy with your plan last year, what you're enrolled in today may look very different in 2026.
Here is a scenario many Medicare enrollees find familiar: you signed up for a Medicare Advantage plan two or three years ago, picked a doctor you liked, confirmed your prescriptions were covered, and moved on. Problem solved, right? Not quite. Under Medicare rules, your plan can legally change its premiums, its list of covered drugs (called a formulary), its in-network providers, and its cost-sharing structure every single year. If you do not review your coverage during the Annual Enrollment Period (AEP), which runs from October 15 through December 7, you roll into the new year on whatever terms your plan has set - not necessarily the terms you remember agreeing to.
This guide walks through exactly what can change in your Medicare coverage from one year to the next, what documents to gather before comparing plans, and how to use the official Medicare Plan Finder tool step by step. An annual review is not just for people with problems. It is a routine financial health check that can save you real money and prevent coverage surprises at the worst possible moment.
What the Medicare Annual Enrollment Period Actually Covers
The AEP - sometimes called the Medicare Open Enrollment Period or Medicare AEP 2026 in search results - is the main annual window during which most Medicare beneficiaries can make changes to their coverage. According to Medicare.gov, during this period you may:
Switch from Original Medicare (Parts A and B) to a Medicare Advantage plan (Part C), or vice versa
Switch from one Medicare Advantage plan to another
Join, drop, or switch a standalone Medicare Part D prescription drug plan
Any changes made during this window take effect January 1 of the following year. Changes submitted after December 7 generally cannot be processed for the upcoming plan year.
It is worth clarifying what the AEP does not cover. Medigap (Medicare Supplement) plans operate under different rules. In most states, you can apply for a Medigap plan at any time during the year, but outside of a guaranteed-issue period, insurers can use medical underwriting. If Medigap is part of your consideration, speaking with a licensed insurance agent familiar with your state's rules is an important step.
There is also a separate Medicare Advantage Open Enrollment Period that runs January 1 through March 31 each year. During that window, current Medicare Advantage enrollees can switch to a different Advantage plan or return to Original Medicare with a Part D plan. However, it does not allow switching from Original Medicare into Advantage. The AEP in the fall remains the primary opportunity for the broadest range of changes.
What Can Change in Your Plan Each Year - Even Without Warning
This is the part that surprises most people. Medicare-approved plans are required to notify you of changes each fall through a document called the Annual Notice of Change (ANOC), which plans must mail by September 30. But many enrollees file it away without reading it carefully. Here is what that document - and an annual review - may reveal:
Premium changes: Your monthly plan premium can increase or decrease. For Medicare Advantage plans, some carry a $0 premium, but that figure is not guaranteed year to year.
Formulary changes: Your plan's drug formulary is the list of covered medications and the tier each drug sits on. A drug that was covered last year may be moved to a higher, more expensive tier, require prior authorization, or be dropped from the formulary altogether.
Network changes: Medicare Advantage plans use provider networks (HMO or PPO structures). Your primary care physician, specialist, or preferred hospital may no longer be in-network in the new plan year.
Cost-sharing changes: Copays, coinsurance rates, and out-of-pocket maximums can shift. A plan that charged a $10 copay for a specialist visit may change that to $40.
Extra benefits changes: Vision, dental, hearing, and fitness benefits that Advantage plans often advertise can be reduced or eliminated in any given year.
Understanding how these costs accumulate across a full retirement helps put individual plan decisions in a longer-term context. A seemingly small change in cost-sharing today can compound into a significant figure over a decade or more.
Before You Compare: Gather These Four Items
A productive plan comparison starts with preparation. Before logging into Medicare's Plan Finder or calling 1-800-MEDICARE, gathering the following information tends to make the process significantly more efficient:
Your current plan's ANOC: This document, mailed in September, outlines every change your plan is making. It is the most direct way to understand what is shifting for the coming year without having to search for it.
A current list of your prescriptions: Write down the name, dosage, and frequency of every medication you take regularly. The Plan Finder uses this list to calculate your estimated annual drug costs across different Part D and Advantage plans. Accuracy here matters considerably.
Your preferred doctors and facilities: Note the names of your primary care physician, any specialists you see regularly, and the hospital or health system you prefer. You will use these to check network status in any plan you consider.
Your Medicare number: Found on your red, white, and blue Medicare card. You will need this to log into or personalize results on Medicare.gov.
One additional consideration worth noting: if you are subject to IRMAA (Income-Related Monthly Adjustment Amount), your Medicare Part B and Part D premiums are already higher than the standard rate based on your income. Understanding how IRMAA interacts with your broader tax picture can be relevant when evaluating the total cost of your Medicare coverage for the year ahead.
Step-by-Step: Using the Medicare Plan Finder to Compare Medicare Plans 2026
The official Medicare Plan Finder, available at medicare.gov/plan-compare, is the authoritative tool for comparing Medicare Advantage and Part D plans available in your zip code. The following walkthrough reflects how the tool is generally structured, though specific interface details may be updated by CMS from year to year.
Step 1 - Enter your location and Medicare information. The tool begins by asking for your zip code and Medicare type. If you log in with your Medicare.gov account, the tool can pull in your current enrollment and, in some cases, your claims history to personalize results.
Step 2 - Enter your prescriptions. Use the drug entry feature to add every medication on your list. The Plan Finder will then calculate estimated annual drug costs for each plan, factoring in your specific drugs, dosages, and the plan's formulary and cost-sharing structure. This is one of the most valuable functions of the tool, because a plan with a low monthly premium can sometimes cost more overall if your medications fall on higher tiers.
Step 3 - Filter by plan type. You can filter results by Medicare Advantage (with or without drug coverage), standalone Part D plans for use with Original Medicare, and by features such as whether a plan includes dental or vision. Consider filtering by your preferred drug pharmacy if prescription pickup logistics matter to you.
Step 4 - Check provider networks. For any Advantage plan you are considering, use the plan's provider directory (linked from the Plan Finder results) to confirm your doctors and preferred hospital are in-network. This step is not optional - it directly affects whether you can continue seeing your current providers without higher out-of-pocket costs or referrals.
Step 5 - Compare total estimated annual costs, not just premiums. The Plan Finder provides a summary of estimated total annual costs for each plan, combining premiums, deductibles, and expected drug costs based on your prescription list. Comparing this total cost figure across two or three finalist plans gives a much clearer picture than monthly premium alone.
Step 6 - Review star ratings. CMS publishes annual Medicare star ratings (on a 1 to 5 scale) for Medicare Advantage and Part D plans. These ratings reflect member satisfaction, customer service, managing chronic conditions, and other quality measures. Star ratings are one data point among many, but they can help distinguish between plans with similar cost structures.
Common Misconceptions About Switching Medicare Plans
A few persistent myths tend to discourage enrollees from reviewing their coverage each year. Addressing them directly may help clarify what is actually at stake.
"I've been happy with my plan, so I don't need to review it." Satisfaction with a plan in the current year does not mean the plan will be identical next year. Network changes, formulary updates, and premium increases can all affect your experience without any action on your part. An annual review is a way to confirm that what you liked about the plan still applies, or to identify a better-fitting alternative.
"Switching plans is complicated and risky." Switching Medicare Advantage or Part D plans during AEP is a standard, well-supported process. Your new coverage begins January 1, your old coverage ends automatically, and there is no penalty for switching. The process is designed to be accessible, and 1-800-MEDICARE (1-800-633-4227), available 24 hours a day, 7 days a week, can assist with questions.
"My employer or union handles this for me." If you receive retiree health benefits from a former employer or union, your coverage situation may differ from standard Medicare enrollment. In some cases, your retiree plan coordinates with Medicare, and you may have a separate enrollment process or fewer choices available. Checking with your plan administrator before making any changes during AEP is an important step in this situation.
"Missing the deadline means I can wait until next year." If you miss the December 7 deadline, your options to change plans become limited until the next AEP (with the exception of the January-March Medicare Advantage Open Enrollment Period, and certain Special Enrollment Periods triggered by qualifying life events). Staying attentive to the fall window helps preserve your options.
What is the Medicare Annual Enrollment Period (AEP) and when does it run in 2026?
The Medicare Annual Enrollment Period runs from October 15 through December 7 each year. During this window, current Medicare enrollees can switch Medicare Advantage plans, switch standalone Part D drug plans, move between Original Medicare and Medicare Advantage, or add or drop drug coverage. Any changes made during AEP take effect January 1 of the following year. This is the primary enrollment window available to most beneficiaries and is distinct from the Medicare Advantage Open Enrollment Period (January 1–March 31), which has more limited options.
Can I switch from Medicare Advantage back to Original Medicare during AEP?
Yes. During the Annual Enrollment Period, you can disenroll from a Medicare Advantage plan and return to Original Medicare (Parts A and B). If you choose to return to Original Medicare, you may also want to add a standalone Part D prescription drug plan during the same window to maintain drug coverage. One important note: if you wish to also add a Medigap (Medicare Supplement) policy, you will generally need to apply separately, and in most states outside of a guaranteed-issue period, insurers may review your medical history. Discussing the Medigap timing and eligibility rules with a licensed insurance agent or your State Health Insurance Assistance Program (SHIP) can help clarify your options.
What is a Medicare plan's Annual Notice of Change, and why does it matter?
The Annual Notice of Change (ANOC) is a document that Medicare-approved plans are required to mail to all enrollees by September 30 each year. It details every change the plan is making for the upcoming plan year, including changes to premiums, deductibles, cost-sharing, covered drugs (formulary), and provider networks. Reading your ANOC before the AEP opens on October 15 gives you a clear starting point: you will know exactly what is changing in your current plan before you decide whether to stay or explore alternatives. If you did not receive your ANOC, you can contact your plan directly or call 1-800-MEDICARE.
Medicare coverage decisions sit at the intersection of healthcare, income, and long-term financial planning. The Annual Enrollment Period is a limited but genuinely meaningful opportunity to make sure your coverage continues to match your needs and your budget. Even a brief, structured annual review using your ANOC and the Medicare Plan Finder can identify changes worth acting on - or confirm that staying put is the right call for now.
This article is provided for general informational and educational purposes only. It does not constitute personalised financial, tax, or insurance advice. Medicare rules, plan availability, costs, and regulations change annually. We encourage you to consult with a qualified financial adviser, a licensed insurance professional, or your local State Health Insurance Assistance Program (SHIP) before making any decisions about your Medicare coverage. You can find free SHIP counseling in your state at shiphelp.org.
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