Medicare Open Enrollment: When Is It and What Can You Change?
Medicare Open Enrollment runs every year from October 15 through December 7. During this period, you can review and change Medicare Advantage and Medicare Part D drug coverage. Changes generally take effect January 1 of the following year, as long as the plan receives your enrollment request by December 7. What you can change depends on whether you have Original Medicare, a Medicare Advantage Plan, or drug coverage now.
When is Medicare Open Enrollment?
Medicare Open Enrollment is the yearly period from October 15 through December 7. It is sometimes called the Annual Enrollment Period.
If you make a change during Open Enrollment, the new coverage generally starts January 1 of the next year. For example, changes made during 2026 Open Enrollment would generally start January 1, 2027, if the plan receives the request by December 7.
What can you change during Medicare Open Enrollment?
The changes available to you depend on your current coverage. In general, during Medicare Open Enrollment you may be able to:
- Switch from Original Medicare to a Medicare Advantage Plan.
- Switch from a Medicare Advantage Plan back to Original Medicare.
- Join, drop, or switch Medicare Advantage Plans, with or without drug coverage.
- Join, drop, or switch a Medicare Part D prescription drug plan if you have Original Medicare.
- Add or drop drug coverage through a Medicare Advantage Plan, depending on the plan options available to you.
Original Medicare means Medicare Part A and Part B. Medicare Advantage, also called Part C, is an alternative way to receive Medicare benefits through a private plan approved by Medicare. Part D is Medicare prescription drug coverage.
What if you keep your current Medicare plan?
If you are satisfied with your current Medicare health and drug coverage, you may not need to take action during Open Enrollment. However, plans can change their costs, covered drugs, pharmacy networks, provider networks, and benefits for the next year.
It is a good idea to review any plan notices you receive and compare your current coverage with other available options before deciding whether to stay or switch.
Does Medicare Open Enrollment let you freely change Medigap?
Not usually. Medicare Open Enrollment mainly applies to Medicare Advantage and Medicare drug coverage changes. Medigap, also called Medicare Supplement Insurance, has separate rules.
Under federal rules, your main Medigap Open Enrollment Period is generally a one-time 6-month period that starts when you are 65 or older and have Medicare Part B. Outside certain protected situations, you may not have a guaranteed right to buy or switch a Medigap policy. State rules may provide additional rights, so availability can depend on where you live.
How is Medicare Advantage Open Enrollment different?
Medicare Advantage Open Enrollment is a separate period from January 1 through March 31. It is only for people who are already in a Medicare Advantage Plan.
During that period, you may be able to switch to another Medicare Advantage Plan or leave Medicare Advantage and return to Original Medicare. If you return to Original Medicare, you may also be able to join a separate Medicare drug plan. This period does not give people with Original Medicare a general opportunity to join Medicare Advantage for the first time.
Are there other times to change Medicare coverage?
Yes, some people qualify for a Special Enrollment Period. These periods are based on certain life events or coverage changes, such as moving, losing other coverage, or changes involving a plan’s Medicare contract.
The timing and types of changes allowed depend on the specific event. If you think you may qualify for a Special Enrollment Period, confirm the rules before making a coverage decision.
From First Meeting to Medicare Enrollment
We begin by helping you understand how Medicare works and how the different pieces fit together. We walk through Original Medicare, Parts A and B, Medicare Advantage, Medicare Supplement insurance, and Part D prescription drug coverage, including how formularies, drug tiers, and plan rules can affect your costs.
We also explain dental, vision, and hearing coverage, along with other products that may help fill gaps in your healthcare plan. Depending on your needs, that may include short-term in-home healthcare coverage, hospital indemnity insurance, or coverage designed to provide additional financial support following a cancer diagnosis, heart attack, or stroke.
Once you understand the landscape, we move into the planning stage. That is when we review your doctors, hospitals, prescription drugs, current coverage, and other personal details so we can begin evaluating the Medicare plan options that fit your situation.
Official Sources
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Open Enrollment | Medicare
Verifies the October 15 to December 7 Open Enrollment dates, January 1 effective date, and major Medicare Advantage and Part D changes allowed. -
Joining a plan | Medicare
Explains that Medicare Advantage and Part D plans can be joined, switched, or dropped only during certain enrollment periods. -
What if I want to switch, drop, or rejoin drug coverage? | Medicare
Verifies rules for switching, dropping, or rejoining Medicare drug coverage during Open Enrollment and when changes take effect. -
Can I switch or drop my Medigap policy? | Medicare
Supports the explanation that Medigap changes have separate rules and may not be guaranteed during Medicare Open Enrollment. -
Special Enrollment Periods | Medicare
Verifies that certain life events may create Special Enrollment Periods and that the changes allowed depend on the situation.
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