Medicare Annual Enrollment Period: 2026 Dates, Deadlines and Checklist

The Medicare Annual Enrollment Period, commonly called AEP or Medicare Open Enrollment, is the fall window when people with Medicare can make certain health and drug plan changes. It runs from October 15 through December 7 every year. For the next cycle, changes you submit by December 7, 2026 take effect on January 1, 2027.

This is not a window to sign up for Medicare Part A or Part B for the first time. Instead, it is primarily the time to review and change your Medicare Advantage coverage or Medicare Part D prescription drug coverage. Medicare plans can change their premiums, copays, drug formularies, provider networks, and supplemental benefits from one year to the next, so a plan that worked well this year may not be the best fit for the next one.

The official Medicare Open Enrollment guidance confirms the annual dates and explains that the plan must receive your enrollment request by December 7.

During AEP, you can join, drop, or switch to another Medicare Advantage plan, with or without prescription drug coverage. You can also move from Original Medicare to Medicare Advantage, or leave Medicare Advantage and return to Original Medicare.

If you are in Original Medicare, you can join, switch, or drop a stand-alone Part D plan. If you leave a Medicare Advantage plan that includes drug coverage and return to Original Medicare, you may need to choose a separate Part D plan so you do not create a gap in prescription coverage. Review the plan's drug list carefully, especially if you take brand-name or specialty medications. Our Medicare prescription drug coverage guide explains the role Part D plays in your overall coverage.

You do not have to make a change just because AEP is open. If your current plan is still offered and continues to fit your situation, keeping it can be the right decision.

Start with the Annual Notice of Change, often called the ANOC, and the Evidence of Coverage, often called the EOC. Plans send these materials before the fall enrollment season. They show whether your premium, deductible, copays, drug coverage, provider network, pharmacy network, benefits, or plan service area will change next year.

Then review your actual use of care. Make a list of your prescription drugs, preferred doctors and specialists, preferred pharmacies, upcoming procedures, and benefits you value such as dental, vision, hearing, transportation, or fitness. Use the official Medicare Plan Compare tool to enter your drugs and compare plans available in your ZIP code.

A low monthly premium does not always mean a lower total cost. Compare the deductible, drug copays, medical copays, out-of-network rules, and the plan's annual maximum out-of-pocket amount before deciding.

Returning to Original Medicare during AEP can be a good fit for some people, particularly those who want broad provider access. However, it may create two additional decisions. First, you may need a stand-alone Part D plan. Second, you may want to explore Medicare Supplement Insurance, also known as Medigap, to help with Original Medicare's deductibles and coinsurance.

AEP does not create a broad guaranteed right to buy a Medigap policy. In Florida and many other states, insurers can use medical underwriting outside a protected enrollment or guaranteed-issue window. Read our Medigap Open Enrollment guide before assuming a supplement will be available after you leave Medicare Advantage. This timing issue is one of the most important items to resolve before making a switch.

If you miss the AEP deadline, you generally keep your current Medicare Advantage or Part D coverage for the next year, unless you qualify for a Special Enrollment Period because of a qualifying life event. Examples can include moving, losing other qualifying coverage, becoming eligible for Medicaid or Extra Help, or certain plan changes.

If you are already enrolled in Medicare Advantage on January 1, a separate Medicare Advantage Open Enrollment Period runs from January 1 through March 31. That window is more limited. It lets eligible Medicare Advantage members switch to another Medicare Advantage plan or return to Original Medicare, but it is not a second AEP for everyone.

If your concern is Part D coverage or a potential late-enrollment penalty, review our FAQ on the Medicare Part D late-enrollment penalty before dropping drug coverage.