What Does Medigap Cover? Benefits by Plan Type

Medigap covers the cost-sharing obligations Original Medicare assigns to the beneficiary: Part A coinsurance, Part B coinsurance, skilled nursing facility coinsurance and in some plans, Part B excess charges and the Part A deductible of $1,736 in 2026. 

The federal government standardizes all Medigap plans under CMS rules, so the same lettered plan offers identical benefits regardless of which health insurance company sells it. Medigap pays only after Medicare processes and partially pays a claim first.

No Medigap plan covers prescription drugs and beneficiaries who need drug coverage must enroll in a separate Medicare Part D standalone plan. This exclusion has applied to all Medigap plans sold after January 1, 2006. Dental, vision, hearing aids, private-duty nursing and long-term custodial care are also excluded from all 10 standardized plans. These gaps are among the most financially consequential for older beneficiaries.

Ten standardized Medigap plans are sold in most states, each labeled with a letter: A, B, C, D, F, G, K, L, M and N. Plan G covers the most for beneficiaries who became eligible for Medicare on or after January 1, 2020, because Plan F (the prior benchmark) is no longer available to new enrollees. Plan G covers everything Plan F covers except the Part B deductible ($283 in 2026). The best Medicare supplement plans vary in premium cost by insurer and location, while the standardized benefits remain identical across all sellers.

Plan G covers all Medicare-approved cost-sharing obligations except one: the annual Part B deductible of $283 in 2026. Every other category, including the Part A inpatient deductible of $1,736 per benefit period, Part B coinsurance, skilled nursing facility coinsurance, Part B excess charges, hospice coinsurance, the first three pints of blood, and foreign travel emergency care at 80%, is covered in full. For new Medicare enrollees, no other standardized plan closes more gaps.   

The single uncovered cost means a Plan G holder pays $283 once per calendar year before Part B benefits activate, then owes nothing further on Medicare-approved services for the rest of that year, assuming providers accept Medicare assignment. Beneficiaries who see physicians billing Part B excess charges above Medicare's approved rate are fully protected under Plan G, because Plan G covers those excess charges in full, a benefit Plan N does not include.

Plan N covers most of what Plan G covers, with two structural differences that determine whether it is the right choice. First, Plan N does not cover Part B excess charges, meaning beneficiaries who see non-participating providers can owe up to 15% above Medicare's approved rate on top of any other cost-sharing. Second, Plan N applies copays of up to $20 for office visits and up to $50 for emergency room visits that do not result in inpatient admission.

What Plan N Covers and Does Not Cover 

Covered by Plan N:

• Part A coinsurance and hospital costs (up to 365 additional days after Medicare benefits end)
• Part A deductible ($1,736 per benefit period in 2026)
• Part A hospice care coinsurance or copays
• Skilled nursing facility coinsurance
• Part B coinsurance (the 20% Medicare assigns after the deductible), except where the copay structure applies
• First three pints of blood
• Foreign travel emergency care (80%, after $250 deductible, up to $50,000 lifetime) 
  

Not covered by Plan N:

• Part B excess charges (non-participating providers may bill up to 15% above Medicare's rate)
• Medicare Part B deductible ($283 in 2026)
• Prescription drugs (requires a separate Part D plan)
• Dental, vision and hearing

Medigap premiums range from $61 to $354 per month depending on the plan letter, your age and your state. The average at age 65 is $189 per month, rising to $238 by age 75, an increase of nearly $588 per year from aging alone. Identical plan letters can differ by hundreds of dollars between insurers in the same state. MoneyGeek's analysis of Medicare supplement plan costs shows that comparing at least three insurers during your Open Enrollment Period is the most effective way to reduce premiums without changing benefits.

Plans C and F are not available to beneficiaries who became eligible for Medicare on or after January 1, 2020. High-deductible figures reflect the 2026 deductible of $2,950 as per CMS.

The right Medigap plan depends on how often you use health care, whether your providers accept Medicare assignment and how much premium certainty you need. Plan G is the benchmark for new enrollees who want comprehensive coverage with no claim surprises. Plan N suits beneficiaries whose providers always accept assignment and who have infrequent specialist visits. Plans K and L fit those who want a lower monthly cost and can absorb a defined share of cost-sharing.

The Medigap Open Enrollment Period begins the first month you are both 65 or older and enrolled in Medicare Part B. The Open Enrollment Period lasts six months and is the only window when insurers cannot deny a Medigap policy or charge more because of a pre-existing condition, regardless of health status. After the Open Enrollment Period closes, insurers in most states can use medical underwriting to decline your application. Enrolling during this window is the single most important timing decision in Medicare supplement plan selection.

Medigap and Medicare Advantage are structurally different approaches to supplementing Original Medicare. Medigap works alongside Original Medicare, you see any provider who accepts Medicare and the plan pays cost-sharing. Medicare Advantage replaces Original Medicare with a private plan that typically restricts you to a network. 

In 2026, Medicare Advantage plans averaged a $0 monthly premium in many markets but came with network restrictions and prior authorization requirements that Medigap avoids entirely. The right choice depends on how much you value provider freedom versus premium savings.

Beneficiaries who prioritize coverage predictability and unrestricted provider access generally benefit more from Medigap. Those whose primary concern is premium cost and who are comfortable with network restrictions often find Medicare Advantage plans more competitive. The decision should account for both current health status and likely specialist use in the next five years.

Medigap picks up what Original Medicare leaves unpaid, but how much it covers depends entirely on the plan letter you select. Plan G closes the most gaps for new enrollees. Plan N costs less but leaves two copay exposures open. No Medigap plan covers drugs, dental or vision. Your Open Enrollment Period window is the time to lock in guaranteed-issue access.

Medigap coverage raises different questions depending on plan type, health status and enrollment timing. The frequently asked questions below address the most common scenarios directly: