Start with Original Medicare
Original Medicare is Part A (hospital care) and Part B (doctors and outpatient care). You can see any doctor or hospital that takes Medicare, anywhere in the U.S. It leaves gaps: you pay a share of most bills, there is no yearly limit on what you pay out of pocket, and for drug coverage you join a separate drug plan. Medicare Advantage and Medigap are two different answers to those gaps, and you can have one or the other, not both. If you'd like someone to walk through it with you, that's what we do.
Medicare Advantage (Part C)
A Medicare Advantage plan comes from a private company that Medicare has approved, and it is another way to get your Part A and Part B benefits instead of Original Medicare. The plan must give you at least the same coverage as Original Medicare. Most plans include drug coverage, and most offer extra benefits such as vision, hearing and dental. You may need to use doctors in the plan's network and get approval before certain drugs or services; in an HMO you generally must use the network except for emergencies and urgent care away from home, and you usually need a referral to see a specialist. Plans have a yearly limit on what you pay out of pocket, and once you reach it the plan pays 100% of covered services for the rest of the year. You keep paying your Part B premium, and if the plan charges a premium, you pay that too.
Medicare Supplement (Medigap)
A Medigap policy is also sold by a private company, but it is a supplement to Original Medicare rather than a replacement for it. When you get care, Medicare pays its share of the Medicare-approved amount first. Then the policy pays whatever you owe under it, and you pay anything left. Policies are standardized and in most states named by letters, like Plan G or Plan K, and price is the only difference between policies with the same letter sold by different companies. Medigap plans sold after 2005 don't include drug coverage, so you join a separate Part D plan if you want it. You pay the Part B premium, the Medigap premium and, if you add one, the drug plan's monthly premium.
Side by side
Doctors and hospitals
With Advantage, you may need to stay in the plan's network and get approvals. With Medigap, you can see any doctor or hospital in the U.S. that takes Medicare.
Prescriptions
With Advantage, most plans include drug coverage, and in most types you can't join a separate drug plan. With Medigap, drug coverage is not included, so you add a Part D plan.
Dental, vision and hearing
With Advantage, most plans offer some of these extras, and the details vary by plan. Medigap generally does not cover vision or dental care or hearing aids.
What you pay for care
With Advantage, the plan decides what you pay for covered services, up to its yearly out-of-pocket limit. With Medigap, the policy pays some or all of your share of Original Medicare costs, and the benefits are different in each plan.
Monthly premiums
With Advantage, each plan sets its own premium, and you still pay Part B. With Medigap, you pay Part B, the Medigap premium and a drug plan premium if you add one.
Travel
With Advantage, care outside the network may not be covered, or may cost more, unless it is emergency or urgent care. With Medigap, you can use any provider in the U.S. that takes Medicare, and some policies cover emergency care when you travel outside the U.S.
Timing matters more for Medigap
You get a six-month Medigap Open Enrollment Period, starting the first month you have Part B and are 65 or older. During it, a company can't refuse to sell you any policy it offers, and it can't charge you more because of health problems you already have. After it, a company is allowed to deny you a policy if you don't meet its medical underwriting requirements. The period happens once; it doesn't repeat every year. Medicare Advantage is different: you can change plans each fall during the Open Enrollment Period, October 15 to December 7. If you drop a Medigap policy to join a Medicare Advantage plan for the first time, you have a single 12-month trial period to get that policy back if the same company still sells it. In certain other situations a company can't deny you a Medigap policy; Medicare.gov calls these Medigap protections, and we can check whether one applies to you.
Questions that usually decide it
Do you want to keep certain doctors?
Check whether they are in a plan's network, or simply whether they take Medicare, which is all Medigap needs.
Do you travel or split the year between two homes?
A network built around one area may not fit. Medigap works with any provider in the U.S. that takes Medicare.
Would you rather pay more each month or more when you get care?
Compare the whole year, not just the premium: with Medigap, a monthly premium for a policy that pays some or all of your share; with Advantage, the plan's premium and its copays as you use care, up to its yearly limit.
Are you still in your Medigap Open Enrollment Period?
If you are, you can enroll in any Medigap policy, and a company can't turn you down for your health. The period happens once.
Drug coverage matters on both paths. See what Medicare Part D covers, or get a free review of the plans we offer with your doctors and prescriptions checked.
Common questions
Can I have Medicare Advantage and Medigap at the same time?
Does Medigap cover prescriptions?
Do I still pay the Part B premium with Medicare Advantage?
Can I leave Medicare Advantage and go back to Original Medicare?
Are all Medigap plans with the same letter the same?
Does it cost anything to talk with you?
Not sure which path fits you?
Licensed agents serving clients nationwide. Our help is free to you.
Get your free reviewSources (14)
Medicare.gov: Your coverage options
Medicare.gov: Parts of Medicare
Medicare.gov: Medicare costs
Medicare.gov: Your health plan options
Medicare.gov: Understanding health plan costs
Medicare.gov: Health Maintenance Organizations
Medicare.gov: Part B
Medicare.gov: How Medigap works
Medicare.gov: Medigap basics
Medicare.gov: What Medigap covers
Medicare.gov: Get ready to buy Medigap
Medicare.gov: Joining a plan
Health insurance (NAIC consumer guide)
SHIP Medicare FAQ (SHIP National Technical Assistance Center)
Last reviewed October 2026. Medicare rules and dates can change; Medicare.gov has the official details.