Medicare Supplement Insurance (Medigap) helps cover out-of-pocket costs that Original Medicare does not pay, such as copayments, coinsurance, and deductibles. But unlike the Medigap Open Enrollment Period -- when insurers must sell you any policy they offer regardless of your health -- buying a Medigap plan at other times can be difficult. Insurers may review your medical history, charge higher premiums, or deny your application altogether.
There is an important exception. Under federal law, certain life events trigger what are known as guaranteed issue (GI) rights. When you have a guaranteed issue right, a Medigap insurer cannot refuse to sell you a policy, cannot charge you more because of health problems, and cannot impose a waiting period for pre-existing conditions. Understanding when these rights apply -- and acting within the required deadlines -- can make the difference between getting the supplemental coverage you need and being locked out of it.
The Medigap Open Enrollment Period: Your Best Opportunity
Before diving into guaranteed issue situations, it helps to understand the most favorable enrollment window available to most beneficiaries.
Your Medigap Open Enrollment Period is a one-time, six-month window that begins the month you are both age 65 or older and enrolled in Medicare Part B. During this period:
- You can enroll in any Medigap policy sold in your state.
- The insurer cannot deny you coverage for any reason.
- The insurer cannot charge you a higher premium based on your health status.
- If you have a pre-existing condition, the insurer may impose a waiting period of up to six months, but it must still sell you the policy.
This open enrollment period does not repeat. Once it closes, your next opportunity to buy a Medigap policy without medical scrutiny depends on whether you qualify for a guaranteed issue right or live in a state with additional protections.
What Guaranteed Issue Rights Protect You From
When you have a federally recognized guaranteed issue right, Medigap insurers must:
- Sell you a policy -- they cannot turn you down.
- Charge the same price they would charge a healthy applicant of your age -- they cannot add surcharges for health conditions.
- Cover pre-existing conditions without a waiting period, provided you had at least six months of prior creditable coverage. If you had fewer than six months of creditable coverage, the insurer can impose a waiting period, but it must be reduced by the number of months of creditable coverage you did have.
These protections exist so that people who lose coverage through no fault of their own are not left without access to supplemental insurance.
All Federal Guaranteed Issue Situations
Federal law establishes specific situations that trigger guaranteed issue rights. In most of these situations, you must apply for a Medigap policy no later than 63 days after your previous coverage ends. The plans available under GI rights typically include Medigap Plans A, B, D, G, K, and L (and Plans C and F if you were first eligible for Medicare before January 1, 2020).
1. Your Medicare Advantage Plan Leaves Your Area or Stops Operating
If your Medicare Advantage (MA) plan stops providing coverage in your area, or if the plan itself is terminated, you have a guaranteed issue right to purchase a Medigap policy. This applies whether the plan pulls out of your county entirely or simply reduces its service area so that your address is no longer covered.
2. You Move Out of Your Medicare Advantage Plan's Service Area
Medicare Advantage plans operate within defined geographic areas. If you move to a location outside your plan's service area, you lose access to that plan. In this situation, you have guaranteed issue rights to buy a Medigap policy in your new area -- even if other Medicare Advantage plans are available there.
3. You Exercise Your Medicare Advantage "Trial Right"
Federal law provides two distinct trial rights:
- First-time MA enrollee at 65: If you enrolled in a Medicare Advantage plan when you first became eligible for Medicare at age 65, you can leave that plan within the first 12 months and return to Original Medicare. When you do, you have a guaranteed issue right to buy a Medigap policy.
- Switched from Medigap to MA for the first time: If you dropped a Medigap policy to join a Medicare Advantage plan for the first time and decide within the first 12 months that it is not the right fit, you can return to Original Medicare. You are guaranteed the right to get back the same Medigap policy you had before -- or, if that specific policy is no longer available, any Medigap Plan A, B, D, G, K, or L sold in your state.
These trial rights recognize that choosing between Original Medicare with a supplement and Medicare Advantage is a significant decision, and beneficiaries deserve the chance to reverse course without being penalized.
4. Your Employer or Union Group Health Coverage Ends
If you have been supplementing Medicare with an employer-sponsored or union group health plan (including retiree coverage or COBRA) and that coverage ends -- whether because the employer stops offering it, you exhaust your COBRA benefits, or the plan itself is discontinued -- you have a guaranteed issue right to purchase a Medigap policy.
This right does not apply if you voluntarily dropped the coverage or stopped paying premiums. The loss of coverage must be involuntary.
5. Your Medigap Insurance Company Goes Bankrupt or Misleads You
If the company that sold you your Medigap policy becomes insolvent, or if you were misled about the policy's benefits when you purchased it, you have a guaranteed issue right to buy a new Medigap policy. This protection also applies if you dropped your Medigap policy because your insurer did not follow its own rules or the rules of its contract with you.
6. You Leave a Medicare SELECT Policy Because You Move
Medicare SELECT is a type of Medigap policy that requires you to use specific hospitals and, in some cases, specific doctors to receive full benefits. If you move out of the Medicare SELECT plan's service area, you have guaranteed issue rights to purchase a standard Medigap policy.
7. You Drop a Medigap Policy to Join a Medicare Advantage Plan or Program of All-Inclusive Care for the Elderly (PACE) -- and the Plan Loses Coverage or Leaves Your Area
If you left a Medigap policy to join an MA plan or PACE program, and then your MA plan or PACE organization stops covering your area or ceases operations, you have guaranteed issue rights. In some cases you may be entitled to return to your original Medigap policy.
What Happens Outside of Guaranteed Issue Periods
If you do not have a guaranteed issue right and your Medigap Open Enrollment Period has passed, buying a Medigap policy becomes considerably more difficult. Here is what you may face:
Medical Underwriting
The insurer will review your health history through a process called medical underwriting. This typically involves a health questionnaire that asks about current and past medical conditions, prescription medications, recent hospitalizations, and upcoming surgeries or treatments.
Possible Denial
Based on the underwriting review, the insurer can deny your application entirely. Conditions such as diabetes, heart disease, COPD, cancer history, or recent joint replacements commonly lead to denial in the individual Medigap market.
Higher Premiums
Even if the insurer approves your application, it may charge a higher premium based on your health status. These surcharges vary by insurer and state but can be substantial.
Pre-Existing Condition Waiting Periods
The insurer may impose a waiting period of up to six months during which it will not pay for services related to a pre-existing condition -- a health problem that was diagnosed or treated during the six months before your Medigap coverage began.
If you had prior creditable coverage (such as employer insurance, Medicare Advantage, or another Medigap plan) with no gap of more than 63 days, the waiting period is shortened by one month for each month of prior coverage. With six or more months of continuous creditable coverage, the waiting period is eliminated entirely.
The 63-Day Creditable Coverage Rule
The 63-day rule is central to Medigap enrollment, and it appears in two important contexts:
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Deadline to apply under guaranteed issue: In most GI situations, you must apply for a Medigap policy within 63 days of losing your previous coverage. Miss this window, and you lose your guaranteed issue right.
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Break in creditable coverage: If you go more than 63 days without creditable coverage, a Medigap insurer can impose the full six-month pre-existing condition waiting period, regardless of how much prior coverage you had.
Keeping continuous coverage -- and acting promptly when coverage changes -- is one of the most important steps you can take to protect your Medigap enrollment options.
State Protections That Go Beyond Federal Law
Federal guaranteed issue rights set the floor, not the ceiling. Many states have enacted additional protections that expand when and how you can purchase Medigap policies.
Continuous or Annual Open Enrollment States
A small number of states require Medigap insurers to sell policies to eligible Medicare beneficiaries age 65 and older at any time, regardless of health status:
- Connecticut: Continuous guaranteed issue year-round. Insurers must sell you any Medigap policy at any time without medical underwriting.
- New York: Continuous guaranteed issue year-round, similar to Connecticut.
- Massachusetts: Requires an annual guaranteed issue period (February 1 through March 31). In practice, insurers in the state offer continuous enrollment throughout the year.
- Maine: Requires an annual open enrollment option for Medigap enrollees.
If you live in one of these states, your access to Medigap policies is significantly broader than federal minimums.
Birthday Rule States
A growing number of states -- now approximately 15 and counting -- have enacted a birthday rule that gives existing Medigap policyholders an annual window around their birthday to switch to a different Medigap plan without medical underwriting. The specifics vary by state, but generally:
- The window lasts 30 to 63 days, typically starting on or around your birthday.
- You can switch to a plan of equal or lesser coverage (some states allow any plan).
- Some states allow switching insurers, while others only allow changes within your current insurer.
States with birthday rules as of 2026 include California, Idaho, Illinois, Louisiana, Missouri, Nevada, Oregon, Virginia, Kentucky, Utah, Indiana, Wyoming, Delaware, Rhode Island, and others. Check with your State Insurance Department for the current rules in your area.
How to Exercise Your Guaranteed Issue Rights
If you believe you have a guaranteed issue right, take these steps:
1. Confirm your qualifying event. Review the federal situations listed above and determine which one applies to you. Keep documentation such as termination notices, plan discontinuation letters, or proof of your move.
2. Note your deadline. In most cases, you have 63 days from the date your previous coverage ends. Mark this date clearly and do not wait until the last minute.
3. Contact Medigap insurers in your area. Tell them you are applying under a guaranteed issue right and specify the qualifying event. The insurer may ask for documentation.
4. Apply for your preferred plan. Under GI rights, you are generally entitled to Plans A, B, D, G, K, or L (and C or F if you were first eligible for Medicare before 2020). If your qualifying event is the MA trial right and you previously held a Medigap policy, you may be entitled to your exact former plan.
5. Get help if needed. Your State Health Insurance Assistance Program (SHIP) provides free, unbiased counseling on Medicare-related insurance questions, including guaranteed issue rights. You can also call 1-800-MEDICARE (1-800-633-4227) or visit Medicare.gov for guidance.
Common Mistakes to Avoid
Missing the 63-day deadline. This is the most consequential error. Once the 63-day window closes, your guaranteed issue right expires, and you are subject to medical underwriting. Set a reminder well before your deadline.
Assuming you can always switch Medigap plans. Outside of your initial open enrollment, guaranteed issue situations, and any applicable state protections, switching from one Medigap plan to another requires medical underwriting. For details on how the risks compare, see our guide on the risks of switching from Medicare Advantage to Medigap. A change that seems simple -- moving from Plan G to Plan N, for example -- can result in denial if you have developed health conditions since you first enrolled.
Confusing Medicare Advantage enrollment periods with Medigap rights. The Annual Enrollment Period (October 15 through December 7) and the Medicare Advantage Open Enrollment Period (January 1 through March 31) are for Medicare Advantage and Part D plans. They do not create guaranteed issue rights for Medigap. Leaving a Medicare Advantage plan during these periods does not automatically give you the right to buy a Medigap policy without underwriting unless one of the specific federal GI situations applies.
Dropping existing coverage before securing new coverage. If you cancel your current Medigap or other supplemental coverage before a new policy is in place, you risk a gap that could exceed 63 days and jeopardize both your guaranteed issue rights and your creditable coverage protections.
Not checking state-specific rules. Your state may offer protections -- such as a birthday rule or broader open enrollment rights -- that give you options beyond federal minimums. Contact your State Insurance Department or SHIP counselor to find out what applies in your area.
Making the Most of Your Enrollment Rights
Guaranteed issue rights exist to protect Medicare beneficiaries during vulnerable transitions -- when a plan disappears, an employer drops coverage, or a new Medicare Advantage plan turns out to be a poor fit. These rights ensure that you can access Medigap coverage when you need it, without being penalized for health conditions.
The key to making the most of these protections is awareness and timing. Know which situations qualify, keep your documentation organized, and act within the 63-day window. If you are approaching 65 and enrolling in Part B, your initial six-month Medigap Open Enrollment Period is by far the most favorable time to secure a policy -- take advantage of it, even if you are not sure you need supplemental coverage right away.
For personalized guidance, contact your SHIP at Medicare.gov or call 1-800-MEDICARE (1-800-633-4227). These resources can help you understand your rights, compare available plans, and make informed decisions about your Medicare coverage.