Medigap is not something you can buy at any time on the same terms. When you buy it - and under what circumstances - has a significant impact on whether you can get coverage at all and what you will pay for it. This is one of the more consequential timing decisions in Medicare planning.
What is the Medigap Open Enrollment Period?
The Medigap Open Enrollment Period is a six-month window that begins when you are both age 65 or older and enrolled in Medicare Part B. During this window, insurers must sell you any Medigap plan they offer in your state at standard rates, without considering your health history. This window opens once and does not repeat.
The most favorable window for buying Medigap is the Medigap Open Enrollment Period. According to Medicare.gov, this period lasts six months and begins the month you are both age 65 or older and enrolled in Medicare Part B.
During this window, insurance companies are required to sell you any Medigap plan they offer in your state at their standard rates - without asking about your health history or medical conditions. This is called guaranteed issue, and it means you cannot be denied coverage or charged a higher premium because of a pre-existing condition during this period.
This window opens once and does not repeat. Once your six-month Medigap Open Enrollment Period ends, you generally lose these protections unless a specific exception applies.
What happens if you miss the Medigap Open Enrollment Period?
In most states, once your six-month open enrollment window has passed, insurance companies can use medical underwriting when you apply for Medigap. That means they can ask about your health history, charge you a higher premium, or decline to sell you a policy altogether. Missing this window can make Medigap significantly harder or more expensive to obtain.
In most states, once your Medigap Open Enrollment Period has passed, insurance companies are permitted to use medical underwriting when you apply for a policy. According to Medicare.gov, this means they can:
- Ask about your health history and current conditions
- Charge you a higher premium based on your health status
- Decline to sell you a policy altogether
This can make it significantly harder - and more expensive - to get Medigap coverage if you wait past your open enrollment window. In some cases, people who are in poor health may find they cannot get coverage at the standard rate, or at all.
A small number of states have additional consumer protections beyond the federal minimum that may give you more flexibility. Your state insurance department or a SHIP counselor can tell you what rules apply where you live.
What are guaranteed issue rights and when do they apply?
Guaranteed issue rights give you the ability to buy Medigap without medical underwriting outside of the initial open enrollment period. They generally apply when you lose coverage through no fault of your own - for example, if your Medicare Advantage plan leaves your area, your Medigap insurer goes bankrupt, or retiree coverage ends. You typically have 63 days from when your coverage ends to use these rights.
Outside of the initial open enrollment window, there are specific situations that give you the right to buy Medigap without medical underwriting. These are called guaranteed issue rights, and they generally apply when you lose coverage through no fault of your own.
According to Medicare.gov, guaranteed issue rights typically apply in situations such as:
- Your Medicare Advantage plan is leaving your area or stopping coverage, and you are moving back to original Medicare
- You joined a Medicare Advantage plan when you first became eligible for Medicare and decide within the first year that you want to switch back to original Medicare
- Your Medigap insurer goes bankrupt or your policy ends through no action of your own
- You have retiree or employer coverage that is ending and you are switching to original Medicare
In these situations, you generally have a limited window - typically 63 days from when your coverage ends - to use your guaranteed issue rights. The specific plans available to you under guaranteed issue may be more limited than the full menu available during open enrollment.
Because the rules around guaranteed issue are detailed and the windows are time-limited, consulting a SHIP counselor as soon as you know your coverage situation is changing is strongly advisable.
Can people under 65 on Medicare buy Medigap?
Federal law does not require guaranteed issue rights for people under 65 who qualify for Medicare due to disability. However, some states have enacted their own protections for this group. If you are under 65 and on Medicare, check with your state insurance department or a SHIP counselor to understand what Medigap options may be available to you.
Some people qualify for Medicare before age 65 due to disability. Federal law does not require guaranteed issue rights for people under 65 during their initial Medicare enrollment, though some states have enacted their own protections. If you are under 65 and on Medicare, it is worth checking with your state insurance department or a SHIP counselor to understand what Medigap options may be available to you.
Why does the timing of buying Medigap matter so much?
The period when you turn 65 and enroll in Part B is generally your best and most protected opportunity to get Medigap on favorable terms. If you have health conditions that could complicate underwriting later, enrolling during this window is especially important. Once the window closes, guaranteed coverage at standard rates is no longer automatic in most states.
The practical implication of all of this is straightforward: the period right around when you turn 65 and enroll in Part B is generally your best opportunity to lock in Medigap coverage on the most favorable terms. If you have health conditions that could make underwriting difficult later, enrolling during your open enrollment period matters even more.
This does not mean Medigap is always the right choice - that depends on your broader situation. But if Medigap is something you want to have, the timing of when you pursue it is not arbitrary. Getting it during your open enrollment window avoids the uncertainty of underwriting later.
Getting Help
A SHIP counselor can explain your guaranteed issue rights, clarify what is available in your state, and walk you through how your specific situation affects your options - at no cost.
Find your local SHIP counselor at shiphelp.org or by calling 1-877-839-2675.
Medigap enrollment rules and guaranteed issue rights vary by state and are subject to change. A SHIP counselor can give you personalized guidance on Medicare options in your area at no cost. Find yours at shiphelp.org.