Medicare Supplement (Medigap): The Essentials of Enrollment
How to cover gaps and select your plan with confidence
Reviewed by: Selah Lee, Licensed Insurance Agent.
Medicare Supplement Insurance (Medigap)Medicare Supplement Insurance (Medigap) is designed to provide coverage that Original Medicare (Parts A and B) does not. Medigap policies are purchased in addition to Original Medicare and have their own monthly premiums you'll need to pay. is an additional policy that covers gaps in Original Medicare (Parts A and B)Original Medicare is a fee-for-service health insurance program available to Americans aged 65 and older and some individuals with disabilities. Original Medicare is provided by the federal government and is made up of two parts: Part A (hospital insurance) and Part B (medical insurance)..
Medigap’s six month Open Enrollment Period starts the month you turn 65 and are enrolled in Medicare Part BMedicare Part B is the portion of Medicare that covers your medical expenses. Sometimes called "medical insurance," Part B helps pay for the Medicare-approved services you receive.. During this period, Medigap insurers can’t deny coverage or charge higher rates due to pre-existing conditionsA pre-existing condition is an illness, injury or other medical condition you had before you enrolled in your health insurance policy..
Enrolling on time can save money down the line.
Medicare Supplement Insurance (Medigap) is extra coverage for costs like co-insurance, copayments, and deductibles. It’s a popular option, too; nearly a quarter of Original Medicare beneficiaries also purchase a Medigap policy. 
Do you know when or how to enroll in Medigap? Perhaps more important: Did you know that when you enroll in Supplement Insurance (Medigap) can impact your coverage?
To be eligibleSome health plans require you to meet minimum requirements before you can enroll., you must enroll in Original Medicare (Parts A and B). Most individuals are automatically enrolled in Medicare Part AMedicare Part A, also called "hospital insurance," covers the care you receive while admitted to the hospital, skilled nursing facility, or other inpatient services. Medicare Part A is part of Original Medicare. by their 65 birthday if they’re already receiving Social Security benefits. If you have questions about enrollment into Medicare parts A or B call your local Social Security office. 
The easy answer: as soon as you’re eligible. For traditional Medigap customers, the Medicare supplement open enrollmentMedicare Advantage Open Enrollment: The annual period when individuals enrolled in Medicare Advantage plans can make a one-time plan change to any other Medicare Advantage, Medicare Advantage Part D, Part D Prescription Drug plan or go back to Original Medicare. Medicare Advantage Open Enrollment is from January 1 - March 31. The Open Enrollment Period for under 65 runs from November 1 to December 15. If you don’t enroll by Dec. 15, you won’t be eligible for coverage unless you qualify for a Special Enrollment Period. period lasts for six months. This window begins the month you turn 65 and enroll in Medicare Part B. You must meet both qualifications to be eligible for Medigap’s open enrollment period.
For example, if you turn 65 in January, but your Part B enrollment begins in February, your eligibility begins on Feb. 1 and runs through the end of July.
During your initial Medigap open enrollment period, you have guaranteed issueA condition that provides Medicare Supplement enrollment without going through medical underwriting. rights. Insurers can’t charge higher premiumsA premium is a fee you pay to your insurance company for health plan coverage. This is usually a monthly cost. because of pre-existing conditions or health status. Insurers are required to accept your application for coverage during the open enrollment period. Plus, your coverage is guaranteed renewable if you purchase it at this time, which means it can’t be canceled by the insurer as long as you pay your monthly premium.
You can still purchase Medigap after your open enrollment period, but you may not get the same pricing or coverage levels. Insurers also are allowed to charge more or limit your coverage for pre-existing conditions if you sign up outside of the initial Medigap open enrollment period.
There are a few exceptions, including if you move or must purchase new Medigap coverage. Many states recognize certain life events and may grant Guaranteed Issue Rights to:
- Medicare recipients who lose supplemental coverage through no fault of their own
- Retirees whose former employers cancel their coverage
- Medicare beneficiaries that move to a new state and can’t keep their supplemental coverage
- Beneficiaries who left a Medigap plan to go into a Medicare Advantage plan, but want to return to the Medigap within 12 months of switching
There are two main ways to enroll in Medigap: (1) you can join on your own. Most private insurance companies have access on their websites or by phone; (2) a licensed insurance agent can help you find the right plan and enroll. It does not cost you anything to speak with a GoHealth licensed insurance agent.
How do I know if I’m already enrolled in Medicare Part A?
If you’re receiving Social Security benefits, you’re automatically enrolled in Part A. If you’re not sure, call your state’s Social Security office.
Does Medigap cover my spouse?
Medigap policies only cover the actual policyholder, not spouses. If you and your spouse both need Medigap coverage, you will need to sign up separately and purchase individual policies. You will each have your own Medigap Open Enrollment Periods. These are six-month windows that begin the month your Part B enrollment starts after you turn 65.