Published: December 12, 2019 Updated: September 15, 2026
Medicare Supplement Open Enrollment is a one-time six-month window that starts the month you are at least 65 and enrolled in Part B, when insurers generally must offer available Medigap plans at standard rates without medical underwriting. Guaranteed-issue rights are separate protections that can apply in specific coverage-loss situations, often with a narrower menu of plan letters. Outside those windows, applications may face medical underwriting.
- Medigap OEP lasts six months starting when you are 65+ and on Part B.
- During OEP, insurers generally must sell available state plans at standard rates.
- Guaranteed issue can apply after certain employer, Advantage, or carrier disruptions.
- GI plan choices are often limited to letters such as A, B, C, F, K, or L (per article).
- Outside OEP/GI, carriers may underwrite and can deny or price differently.
Whether you’ve already decided on a Medicare Supplement insurance policy or you’re still weighing your options, you have to purchase your plan at the right time. Learn everything you need to know about Medicare Supplement user rights, and discover the key differences between Medicare Supplement Open Enrollment vs. Guaranteed Issue.
Medicare Supplement Open Enrollment
Every Medicare recipient has what’s known as a Medicare Supplement Open Enrollment Period. This lasts for six months and starts on the first day of the month when you’re at least 65 years old and enrolled in Medicare Part B. Because the start of this six-month period requires you to enroll in Part B, the timing might differ from your Medicare initial enrollment period, which begins three months before your 65th birthday.
During your Medicare Supplement Open Enrollment Period, you’re able to purchase any Medigap policy that’s available in your state. The 10 standardized Medigap policies are available in 47 states, with Massachusetts, Minnesota, and Wisconsin offering slightly different options.
The benefits of buying a Medigap plan during open enrollment are twofold. Not only do insurance companies have to sell you any policy that’s available in your state but they also have to charge you a standard rate. That means providers can’t require you to pay more due to your age or a pre-existing condition.
Not everyone chooses the right Medigap plan on the first attempt. If you want to purchase the same plan from a different provider or you want to change the plan entirely, you can apply for a new plan at any point during the year. If this occurs outside your initial period, you will have to answer health questions to qualify for coverage.
How do I know which enrollment period applies to me?
Medicare Supplement Insurance Guaranteed Issue
- Sell you a Medigap plan: You have the right to purchase a Medigap plan during guaranteed issue periods.
- Cover your pre-existing health issues: Regardless of your pre-existing conditions, Medigap plans obtained through guaranteed issue must provide coverage.
- Charge you the standard Medigap plan rate: Even if you have pre-existing conditions, the insurance company must apply the standard rate for the Medigap plan.
Guaranteed Issue Rights Scenarios:
- Transition from an employer-sponsored group health plan: If you have both Medicare and an employer-sponsored group health plan, and the latter is ending, you have guaranteed issue rights to obtain a Medigap plan.
- Changes to a Medicare Advantage Plan: If you purchased a Medicare Advantage Plan that is leaving Medicare or no longer covers your area, you have the right to switch back to Original Medicare and Medigap within a year.
- Return from a Medigap policy to Medicare Advantage: If you switched from Original Medicare and Medigap to a Medicare Advantage Plan but less than a year has passed, you can exercise your guaranteed issue rights to switch back.
- Disruption in coverage from the Medicare Supplement Insurance company: If your Medicare Supplement Insurance company goes bankrupt or ceases your coverage without fault on your part, you have guaranteed issue rights.
Can You Purchase Medicare Supplement Insurance At Other Times?
If you don’t have an open enrollment period or guaranteed issue rights, insurance companies may use medical underwriting to determine whether to take your application or grant you a policy.
Different Medicare Supplement insurance carriers have different underwriting standards. If you are denied coverage by one carrier, you may still be eligible for coverage with a different one. This is a situation where having an independent agent is huge since they can help you apply for coverage with a variety of Medigap insurance carriers.
For some retirees, it’s worth the effort to purchase a Medigap policy after the open enrollment period and outside of any special conditions. If you’re faced with this decision, take the time to compare the premium costs with your anticipated medical bills. With this calculation in hand, you can make the right choice for your budget, healthcare needs, and peace of mind.
It is a six-month period that begins the first day of the month when you are at least 65 and enrolled in Medicare Part B. Timing can differ from your Medicare Initial Enrollment Period around age 65.
According to the article, companies generally must sell you any Medigap policy available in your state and charge a standard rate -- they cannot charge more because of age or a pre-existing condition during that window.
Open Enrollment usually lets you choose among Medigap plans sold in your state. Guaranteed-issue rights arise in specific situations and typically limit you to certain plan letters (the article lists A, B, C, F, K, or L) while still requiring sale, coverage of pre-existing conditions, and standard rates.
Examples in the article include ending employer group coverage while on Medicare, an Advantage plan leaving Medicare or your area, returning from a first-year Advantage trial after dropping Medigap, or your Medigap insurer ending coverage through no fault of yours. Confirm your situation with official Medicare guidance or a licensed advisor.
Yes, but insurers may use medical underwriting and can deny coverage or vary pricing. Standards differ by carrier, so an independent agent may help you apply with more than one company.
