Medicare Supplement Insurance, also known as Medigap, helps cover out-of-pocket costs that Original Medicare (Part A and Part B) does not pay. These costs can include deductibles, coinsurance, and copayments. However, unlike Original Medicare, which has open enrollment for all eligible individuals, Medigap policies are sold by private insurance companies, and approval is not always guaranteed.
If you’re considering purchasing a Medigap plan, it’s important to understand when you can and cannot be denied coverage. This guide will explain:
- When you are guaranteed acceptance into a Medigap plan
- How medical underwriting can lead to denial
- State-specific rules that offer extra protections
- How Medicare Advantage affects Medigap eligibility
When You Cannot Be Denied a Medigap Plan
The Medigap Open Enrollment Period (OEP)
The best time to buy a Medigap plan is during the Medigap Open Enrollment Period (OEP). This is a six-month window that starts the first month you are both:
- 65 years or older
- Enrolled in Medicare Part B
During this period, insurance companies cannot deny you coverage or charge higher premiums based on your health. Once this window closes, medical underwriting may be required, which could result in a denial or higher costs.
💡 Read our full guide on the Medigap Open Enrollment Period.
Guaranteed Issue Rights (Protections Outside Open Enrollment)
Even if you miss the Open Enrollment Period, you may still qualify for a Medigap policy under Guaranteed Issue Rights. These rights apply if:
- You lose employer or union coverage that was secondary to Medicare
- You move out of your Medicare Advantage plan’s service area
- Your Medicare Advantage plan discontinues coverage
- Your Medigap insurance company goes bankrupt
- You switch from Medicare Advantage back to Original Medicare within the first 12 months (trial right)
In these cases, insurers must sell you a Medigap policy without medical underwriting.
💡 Learn more about Guaranteed Issue Rights.
When You Can Be Denied a Medigap Plan
Applying Outside Open Enrollment (Medical Underwriting Applies)
If you apply for Medigap after your Open Enrollment Period and do not have Guaranteed Issue Rights, insurers can:
- Deny your application based on health conditions
- Charge higher premiums due to medical history
- Impose a waiting period before covering pre-existing conditions
Pre-Existing Condition Waiting Periods
Even if you are approved, some insurers may impose a waiting period of up to six months before covering pre-existing conditions. However, this can be waived if you have had continuous coverage, such as employer health insurance, before applying for Medigap.
State-Specific Rules: Extra Protections in Some Areas
- New York, Connecticut, Massachusetts, and Maine require insurers to offer Medigap coverage year-round with no medical underwriting
- Some states allow people under 65 on Medicare due to disability to buy Medigap policies
- Certain states offer additional enrollment periods for Medigap applicants
The Impact of Medicare Advantage on Medigap Eligibility
Many people assume they can switch between Medicare Advantage and Medigap at any time, but that is not always the case.
- If you are enrolled in a Medicare Advantage plan, you cannot have a Medigap policy at the same time
- Switching from Medicare Advantage back to Original Medicare does not automatically give you Guaranteed Issue Rights for Medigap
- There is a “trial right” exception: If you leave a Medigap plan to try Medicare Advantage for the first time, you can return to Medigap within 12 months
Final Thoughts: Plan Ahead to Avoid Denial
The best way to ensure you get a Medigap policy without denial or increased costs is to apply during your Open Enrollment Period. If you miss this period:
- You may still qualify for coverage under Guaranteed Issue Rights
- Medical underwriting may apply, which could lead to denial or higher premiums
- State-specific rules may offer additional protections
💡 If you are considering a Medigap plan, the best time to apply is as soon as you are eligible.
👉 Speak with a Medicare specialist or licensed insurance agent to explore your best options.
FAQ: Common Questions About Medigap Eligibility
Can I be denied a Medigap plan for having pre-existing conditions?
During your Open Enrollment Period or if you have Guaranteed Issue Rights, insurers cannot deny you coverage for pre-existing conditions. However, if you apply outside of these periods, you may be subject to medical underwriting and potential denial.
What if I miss my Medigap Open Enrollment Period?
You can still apply for Medigap, but insurers can review your health history and may charge higher rates or deny coverage. Some states have additional protections, so check your state’s Medigap rules.
Can I switch from Medicare Advantage to Medigap?
Yes, but you may not have Guaranteed Issue Rights unless you are within your first 12 months of Medicare Advantage coverage (trial right) or qualify for another special enrollment exception.
Are Medigap policies available to people under 65?
Medigap policies are primarily designed for people 65 and older, but some states require insurers to offer plans to those under 65 who qualify for Medicare due to disability.
What if my Medigap insurer goes out of business?
If your insurance company goes bankrupt, you qualify for Guaranteed Issue Rights and can enroll in another Medigap plan without denial.
💡 For more details, contact your State Health Insurance Assistance Program (SHIP) or a licensed Medicare broker.