Why Medigap Isn’t Part of Open Enrollment and When You Can Change It

What Fall Open Enrollment Actually Covers

Medicare’s annual enrollment period, which runs from October 15 through December 7, was created for two kinds of plans: Medicare Advantage plans and Part D prescription drug plans. Those plans are contracts between a private company and the federal government, and they are redesigned every year. Premiums, benefits, networks, formularies and costs can all change on January 1, so Medicare gives everyone a time to review and switch.

A Medigap policy is a different animal. It is a standardized supplement that pays part of what Original Medicare leaves to you. The benefits of each lettered plan are standardized under federal and state rules and are not redesigned each year the way Advantage and Part D plans are. A Plan G sold by one company has the same basic benefits as a Plan G sold by another company. Because the benefits themselves are not reshuffled every year, there is no annual redesign that would call for a formal review period.

The practical result is that Medigap is not touched by Medicare’s fall enrollment rules at all. You do not receive an Annual Notice of Change for it the way Advantage and Part D members do. If you are curious about that document, our post on how to read your annual notice of change explains what it contains for the plans it applies to. Your Medigap insurer will send its own premium notices, with timing that varies by company, and those follow state rules.

For the full list of fall dates and what each lets you do, see our post on the annual enrollment period.

Why Medigap Works Differently

There are three reasons the system treats Medigap differently.

First, Medigap is regulated by states, not by the Medicare program. Each state’s insurance department decides how companies may price and sell policies, and what rights consumers have. That is why the rules can differ from one state to the next, and why a friend in another state might describe a very different experience.

Second, Medigap works on an insurance principle that the structure of Advantage does not. Because it pays costs that follow Original Medicare, its pricing is based on the health of the people in the pool. If people could join and leave freely each year, those who are sick might switch to the most generous plan and those who are healthy might drop coverage, and premiums could rise for everyone. Medical underwriting is the tool insurers use to manage that, and most states allow it outside certain protected windows.

Third, Medigap is guaranteed renewable. If you keep paying your premium, the insurer cannot cancel your policy because of your health or because you used it. That protection means you do not have to re-enroll every year to keep your coverage, so there is no yearly renewal decision the way there is with Advantage and Part D.

What You Can Do When You Want a Change

Path	Health questions?	Notes
Initial six-month window at 65 and Part B	No	The most protected opportunity
Federal guaranteed-issue right	No	Usually 63 days after the qualifying event
Birthday rule in some states	No	Details and eligible plans differ by state
Any other application	Usually yes	Insurer can decline, charge more or add a waiting period

Not having an annual window does not mean you are locked in. It means you apply on the insurer’s terms and under the rules that fit your situation. Here are the realistic paths.

Apply any time, and expect underwriting. You can apply for a Medigap policy at any time of year. If you are outside your initial window and you do not have a guaranteed-issue right, an insurer in most states may ask health questions, may decline the application, may charge more based on your health, or may add a waiting period of up to six months for pre-existing conditions. Outcomes depend on the insurer and on your health history, so approval is never something to assume.

Use your initial six-month window. When you first enroll in Part B at 65 or older, you get a one-time six-month Medigap open enrollment period. Our page on the Medigap open enrollment period describes it. During it, insurers must sell you any policy they offer to your age group, at standard rates, regardless of your health. This is by far the most protected opportunity you will have.

Use a guaranteed-issue right. Federal law gives you the right to buy certain Medigap policies without health questions after specific events. Examples include losing employer or union retiree coverage that supplemented Medicare, leaving a Medicare Advantage plan under certain circumstances, such as the plan ending, you moving out of its service area, or a significant change to its network, and the 12-month trial rights for people who try Advantage for the first time. You generally have 63 days after your prior coverage ends to apply. Our posts on switching from Advantage to Original Medicare and Advantage trial rights describe the Advantage-related ones. Some states add their own events. In Ohio, for example, a person who is disenrolled from Medicaid may qualify for a time-limited guaranteed-issue window.

Use a state-specific rule. A number of states have created extra opportunities. We cover that next.

State Rules That Create Extra Windows

Some states have a so-called “birthday rule,” which lets current Medigap holders switch policies once a year around their birthday without health questions, usually to a plan of equal or lesser benefits. The details differ widely. In some states you can switch only within the same company. In others you can change companies. The window length varies, and some limit it by age.

Some states go further. New York and Connecticut have continuous open enrollment, and Massachusetts has its own distinct rules and plan designs.

Here is how that looks for Ohio and two neighbors, based on the National Association of Insurance Commissioners’ state chart as of mid-2026.

• Ohio does not have a birthday rule. Once your initial window has passed, changing Medigap plans generally requires underwriting unless you have a guaranteed-issue event. Our page on Ohio’s Medigap regulations explains this in detail.
• Kentucky passed a law, effective in 2024, that lets a Medigap enrollee switch to another insurer’s version of the policy they have within 60 days of their birthday. The Kentucky Department of Insurance describes it as a 60-day guaranteed-issue period beginning on the birthday, for the same plan.
• Indiana enacted a law in 2025 creating a birthday-rule window, starting in January 2026, that allows people to move to another insurer’s version of the policy they already have. Because this is new and the window details may have been adjusted since it passed, confirm the current dates and who qualifies with the Indiana Department of Insurance.

If you live in a state with such a rule, it can be a useful tool for shopping when your premium rises. If you live in Ohio, the options are narrower, and you should make decisions about Medigap with the understanding that switching later is not guaranteed.

Should You Shop Around Even Without a Window?

Premiums for Medigap policies can rise over time, and people sometimes wonder whether to look for a new carrier each year. That is understandable, but it deserves some thought.

Before you apply for a replacement policy, find out how your current insurer prices the policy, whether it is attained-age, issue-age or community rated, because that affects how quickly premiums increase. A rate that rises with age is not necessarily a sign of a problem.

If you do apply elsewhere, do not cancel your current policy until you have decided to keep the new one. Medicare’s official Medigap guide says you have a 30-day free look period after you receive the new policy to decide, and that you will pay both premiums for the month you have both. On the application you will have to promise to cancel the first policy, and the guide advises asking for the old coverage to end only after the new policy has been in place for the 30 days. Approval is never guaranteed, since the insurer may use underwriting.

The guide also explains how pre-existing condition waiting periods work when you replace a policy. If you have had your current policy for more than six months and the new one has the same benefits, the new insurer cannot exclude a pre-existing condition or make you wait. If the new policy includes a benefit your current one lacks, you may have to wait up to six months for that benefit, and if you have had your current policy for less than six months, the new insurer must subtract the months you have already had it from any waiting period. Ask any insurer you apply to how it will treat your time on the current policy.

Compare like with like. A Plan G from one insurer has the same basic benefits as a Plan G from another, so the real differences are premium, rating method, the company’s rate-increase history, discounts, and service. Our page on changing your Medigap policy goes through the process, and our comparison of Plan G and Plan N shows why the lettered plans differ in what you pay.

One caution: where birthday rules exist, they usually limit you to a plan with the same or fewer benefits than the one you have, and in some states, including Kentucky and Indiana, to the same plan with a different insurer. Moving to a richer plan typically means going through underwriting.

When People Mix Up the Two Systems

A common mistake each fall is assuming that open enrollment lets you leave Medicare Advantage and buy Medigap without health questions. It does not. Dropping an Advantage plan in the fall returns you to Original Medicare, but your ability to buy Medigap is governed separately, and in most states that means underwriting unless a guaranteed-issue right applies. Do not drop your Advantage plan until you have confirmed you can get the Medigap policy you want.

The reverse can also catch people. If you have a Medigap policy and you join an Advantage plan during open enrollment, Medicare’s guide says you have a legal right to keep the Medigap policy, but it cannot pay Advantage deductibles, copayments, coinsurance or premiums, so many people cancel it. Getting it back later may not be possible unless you are within a trial right.

What Fall Enrollment Means for Each Type of Coverage

The confusion usually comes from lumping every Medicare product together. Here is how the fall period plays out depending on what you have.

If you have Original Medicare with a Medigap policy and no drug plan. The fall period does not touch your Medigap. Your policy continues, your benefits stay the same, and nothing is required of you. What it does offer is a chance to review your Part D drug coverage. Medigap plans sold after 2005 do not include prescription drug coverage, according to Medicare’s Medigap guide, so a standalone drug plan is the place where fall enrollment applies to you.

If you have Original Medicare with Medigap and a drug plan. The drug plan is the piece that changes each year, so the annual notice and the fall window apply to it. Your Medigap does not. Our post on formulary changes explains why checking your drug plan each fall still matters.

If you have Medicare Advantage. Fall enrollment applies in full. You can switch plans or return to Original Medicare. If you return, the Medigap question described in this post becomes the key decision.

If you have Original Medicare and no supplement. You can use fall enrollment to join an Advantage plan, but you cannot use it to obtain a Medigap policy without health questions, because the two are governed by different rules.

If you have an older Medigap policy. Medicare’s guide says that if you have an older policy, you do not have to switch. If you buy a new policy, you must cancel the old one, and once you cancel, you cannot get it back. Policies bought before June 1, 2010 may offer coverage that is not available in newer policies. That is worth considering before you give one up.

A Step-by-Step Way to Change Medigap Policies

If you have decided you want a different Medigap policy, a careful sequence protects you.

• Step 1: Confirm what you have. Locate your current policy, the plan letter, the premium, and how the premium is rated, whether attained-age, issue-age or community-rated.
• Step 2: Decide what you want to change. Is it the price, the company, the benefits, or all three? Moving to a plan with more benefits is a different underwriting question from moving to one with fewer.
• Step 3: Check your state’s rules. Ask your State Insurance Department or State Health Insurance Assistance Program whether a birthday rule, a guaranteed-issue event or a special window applies to you.
• Step 4: Compare the same plan letter across companies. Medicare’s guide notes that the premium is the only difference between policies with the same letter sold by different companies, and that premiums for the same coverage can vary a great deal.
• Step 5: Gather your health information. If underwriting applies, list your diagnoses, medications and treatment dates before you apply.
• Step 6: Apply and state in writing that you will cancel the old policy. The guide says an insurer can sell you a new policy if you state in writing that you plan to cancel your existing one.
• Step 7: Wait for approval. Do not cancel the old policy yet.
• Step 8: Use the free-look period. After the new policy begins, you have 30 days to decide whether to keep it. Cancel the old policy only after you are sure.

Two Scenarios

These are hypothetical, and the details in your state may differ.

Picture a retiree in Ohio whose Medigap premium has climbed each year. They are in good health and wonder whether another company charges less for the same plan letter. Because Ohio has no birthday rule, they apply with full underwriting. They are approved, wait for written confirmation, and cancel the old policy only after the 30-day free-look period ends. If they had been declined, nothing would change for them, since their current policy is guaranteed renewable.

Picture a Kentucky resident with the same goal. According to the National Association of Insurance Commissioners’ chart, Kentucky allows a switch to another insurer’s version of the same policy within 60 days of a birthday. This person would confirm the exact rules, and the plan eligible for the switch, with the Kentucky Department of Insurance before applying.

Costly Mistakes to Avoid

• Canceling before approval. If the new application is declined and the old policy is already canceled, you may be left with nothing. The guide warns that once you cancel an old policy, you cannot get it back.
• Assuming fall enrollment helps with Medigap. It does not, and in most states a switch outside a protected window means underwriting.
• Comparing different plan letters. Compare Plan G to Plan G. Comparing G to N or F mixes benefits with price.
• Judging only by this year’s premium. A lower first-year premium on an attained-age policy may rise faster than another approach.
• Dropping Medigap for Advantage without understanding what you give up. Getting back may require a trial right. Our post on Advantage trial rights describes the window.
• Pressure sales. Medicare’s guide says it is illegal for someone to pressure you to buy a Medigap policy or lie to get you to switch.

What to Ask an Insurer or Agent

• Is this a new policy or a replacement, and will my time on my current policy count toward any waiting period?
• Is the premium attained-age, issue-age or community-rated, and what does the company’s rate history look like?
• Does this plan have the same benefits as my current one?
• Will there be health questions, and how far back do they go?
• When would the policy start, and is there a free-look period?
• Do you have discounts available, and what conditions apply?

What to Do If It Goes Wrong

If an application is declined, you keep your current policy. If you believe an insurer or agent acted improperly, the guide suggests contacting your State Insurance Department, and you can call the Inspector General’s hotline listed in the guide for federal violations. If you canceled a policy and then learned the new one was not approved, call both companies and your State Insurance Department right away to ask what options exist, and do not assume the old policy can be reinstated, since Medicare’s guide says a canceled policy cannot be gotten back. And if you are unsure what rights apply in your state, your State Health Insurance Assistance Program offers free, unbiased counseling.

Frequently Asked Questions

Is there an open enrollment period for Medigap every year?

No. Medigap has a one-time six-month open enrollment period when you first enroll in Part B at 65 or older. After that, you apply on the insurer’s terms unless you have a guaranteed-issue right or live in a state with a special rule.

Does the fall enrollment period let me switch Medigap plans?

No. The fall period covers Medicare Advantage and Part D plans. It does not give you a right to change your Medigap policy without underwriting.

Does Ohio have a birthday rule for Medigap?

No. According to the National Association of Insurance Commissioners’ state chart, Ohio does not. Kentucky and Indiana each have a version, so people near the state line should be sure which state’s rules apply to them.

Can my Medigap insurer cancel my policy if I do not switch?

An insurer generally cannot cancel your Medigap policy because of your health or claims. It can cancel for nonpayment of premium or for material misrepresentation on your application.

Can I move to a cheaper Medigap policy?

You can apply at any time, and in most cases you will be asked health questions. Where a birthday rule exists, it usually allows a move to the same plan, or one with the same or fewer benefits, depending on the state. Elsewhere, approval is never guaranteed.