John Kimelman is a veteran financial journalist who spent 14 years as an executive editor at Barrons.com. In that role, he supervised a staff of writers, edited and wrote online columns, and wrote feature articles and cover stories for Barronâs magazine. Previously, he worked as a staff editor and writer at CNBC.com and American Banker, the leading trade publication of the U.S. commercial banking industry.
As a 30+ year member of the AICPA, Nancy has experienced all facets of finance, including tax, auditing, payroll, plan benefits, and small business accounting. Her résumé includes years at KPMG International and McDonald’s Corporation. She now runs her own accounting business, serving several small clients in industries ranging from law and education to the arts.
Medigap is private health insurance that works alongside Original Medicare. It helps pay costs that Medicare doesnât fully cover, such as co-payments, coinsurance, and deductibles. These policies donât replace Medicareâthey fill in the âgaps.â
How is Medigap different from Medicare Advantage?
 Medicare Advantage is an alternative way to receive your Medicare benefits through a private insurer, typically bundling hospital, medical, and drug coverage into one plan. Medigap, by contrast, only supplements Original Medicare. You canât use both at the same timeâenrolling in one excludes the other.
What benefits do Medigap plans offer?
All Medigap policies are standardized and labeled A through N. Each plan type provides the same set of core benefits no matter which insurer sells it, but premiums vary. Some plans cover nearly all out-of-pocket costs, while others offer lighter coverage at a lower price.
If youâve read even just a little about Medicare, you may have already come across the synonymous terms Medicare Supplement Insurance and Medigap. Supplement insurance is optional, and itâs relevant only for the roughly half of all Medicare recipients who enroll in Original Medicare, which is administered by the federal government.
Medicare Advantage plans are offered by insurance companies who build supplemental coverage into the all-in-one policies they market, so an additional policy isnât needed. In fact, if you select Medicare Advantage, insurance companies arenât allowed to sell you a Medigap policy.
Medigap plans help cover hospital and medical costs not covered by Original Medicare.
These plans are marketed and administered by insurance companies, not the federal Medicare program.
Eighty percent of seniors enrolled in Original Medicare also have some type of supplemental policy.
For many Medicare beneficiaries, supplemental coverage is essential because Original Medicare doesnât cover all their health care expenses. An additional Medigap policy can help fill those gaps, though at the cost of an additional premium. As of 2026, new Medicare cost figures and plan rules shape how Medigap fits into the picture (more on this below).
Health care gaps Medigap coverage can help fill
Original Medicare covers a wide range of health-related services and medical supplies for its beneficiaries. But there are some costs, such as co-payments and deductibles, that can result in substantial out-of-pocket expenses. Medigap can pick up all or most of the out-of-pocket costs that youâd have to pay if all you had was the hospital and medical insurance provided by Parts A and B of Original Medicare.
These Medigap plans are operated and marketed by insurance companies, not the federal Medicare program, although the federal government is responsible for establishing the guidelines that insurance companies must follow.
Some Medigap policies pay for emergency health care received abroad, as Original Medicare doesnât cover medical bills incurred outside the U.S. If foreign travel health coverage matters to you, make sure any Medigap policy you purchase includes it.
Four out of five (80%) adults enrolled in Original Medicare are also enrolled in some type of supplemental policy, according to KFF, the health policy organization formerly known as the Kaiser Family Foundation. Further, more than half receive supplemental coverage through employer-sponsored retiree health plans, union plans, or even Medicaid, the government program that provides health coverage for low-income people.
Some employers and unions are willing to purchase Medigap policies for their employees and retirees. But even if you have to purchase your own policy, itâs worth considering.
Important things to know about Medigap policies
Spouses require separate policies. Like Original Medicare, a Medigap policy only covers one person, so each Medicare beneficiary in your household needs an individual policy.
Comparison shopping pays. You might find identical coverage from another insurance company that costs hundreds of dollars less annually. Premiums can increase as you age. Some states limit Medigap premium costs.
Renewals are guaranteed. Any standardized Medigap policy is required to offer you a renewal, even if you develop health problems while on the policy. The company canât cancel you as long as you continue to make premium payments.
Drug coverage is separate. As of January 6, 2006, Medigap policies stopped covering prescription medications, but you can enroll in Medicare Part D for prescription drug coverage.
Additional coverage may be needed. A Medigap plan wonât cover long-term care, dental, or vision care. You may want to explore separate insurance options for these services.
Understanding the different Medigap plans (A through N)
If you think understanding Parts A, B, C, and Dâthe basic building blocks of the Medicare programâis a bit of a challenge, the variety of Medigap plans can be equally confusing. In all but three states (Wisconsin, Massachusetts, and Minnesota), insurance companies can only sell a standardized Medigap policy identified by letters A through N (although some letters have been discontinued and others are closed to new enrollees). Unlike Medicare parts, which cover different types of care, Medigap plans help cover certain out-of-pocket costs not included in Original Medicare.
Each of the lettered plans offers a different set of benefits, and the costs vary with the amount of coverage. In general, Plan A provides the fewest benefits and has the lowest premiums. Medigap plans that more effectively fill in cost gaps, such as plans F or G, usually have a higher premium. Hereâs a rundown:
2026 costs and coverage updates
Medicare costs change each year, and those shifts affect how Medigap policies fit into a beneficiaryâs budget. In 2026, the standard Part B premium is $202.90 per month, and the Part B deductible is $283. The inpatient hospital deductible under Part A is $1,736.
Some Medigap plans also have built-in cost limits that reset annually. For 2026, the out-of-pocket maximum is $8,000 for Plan K and $4,000 for Plan L (these federal limits are unchanged year to year). High-deductible versions of Plan F and Plan G each carry a deductible of $2,950 before benefits begin.
Although Medigap policies donât cover prescription drugs, Medicare Part D includes an annual out-of-pocket cap of $2,000 in 2026, indexed annually.
Plans A, B, D, G, K, L, M, and N. Still active and open to new enrollees (in most states). Thereâs also a high-deductible version of G.
Plans C and F. Closed to new enrollees since January 1, 2020 (but existing policyholders can keep them). For existing Plan F enrollees, thereâs also a high-deductible version available.
Plans E, H, I, and J. Phased out back in 2010 and no longer available.
Federal guidelines require that each Medigap plan must offer the same basic benefits, no matter which insurance company sells it. So Plan G offered by one insurer provides the same benefits as Plan G offered by another. The prices may differ, but the benefits wonât.
According to the American Association for Medicare Supplement Insurance, the majority of new Medicare enrollees since 2020 have chosen Plan G, which covers nearly all costs except the Part B deductible.
Consider the premium cost to ensure it fits within your budget before choosing a plan.
The bottom line
Whether you get it for free, at a discount from an employer or a union, or pay for it out of your own pocket, some form of supplemental insurance is recommended for enrollees of Original Medicare. If you have no choice but to pay for your own Medigap policy, start by finding a list of supplemental plans offered in your area using the Medigap plan finder.
Your best chance to buy without medical underwriting is during your one-time, six-month Medigap open enrollment period, which begins when you first enroll in Part B. The annual Medicare open enrollment window each fall (October 15 to December 7) is when you can make other changes, such as switching between Original Medicare and Medicare Advantage.
