What Medigap Plans Actually Cover: A Clear Guide to Your Benefits

Understanding what Medigap plans cover can feel confusing when you’re first exploring Medicare options. Medigap (also called Medicare Supplement Insurance) is designed to work with Original Medicare, not replace it—and its main job is to help pay the out‑of‑pocket costs that Medicare Part A and Part B don’t fully cover.

This guide breaks down Medigap coverage in plain language so you can see:

• What Medigap plans typically cover
• What they do not cover
• How coverage can differ between plan types
• How Medigap works with your other Medicare benefits

Medigap Basics: What These Plans Are Designed to Do

Medigap plans are private insurance policies that you can buy if you have Original Medicare (Part A and Part B). Their purpose is to help with:

• Deductibles (what you pay before Medicare starts paying)
• Coinsurance (your share of the bill, usually a percentage)
• Copayments (fixed amounts you pay for certain services)

Think of Medigap as a “gap-filler” for Medicare-covered services. It does not give you new types of medical benefits beyond what Original Medicare already covers, with a few limited exceptions (like foreign travel emergency coverage in some plans).

The Core Costs Medigap Plans Commonly Cover

While each standardized Medigap plan (Plan A, B, C, D, F, G, K, L, M, and N) is different, most are built around the same key cost areas. Here are the main gaps Medigap can help fill.

1. Part A Hospital Coinsurance and Extra Hospital Days

Original Medicare Part A covers hospital stays, but you still face:

• A deductible for each benefit period
• Daily coinsurance if your stay is long

Every Medigap plan must cover the Part A coinsurance and provide coverage for up to 365 additional days in the hospital after your Medicare hospital benefits are used up.

In practical terms:
If you have a long hospital stay, a Medigap plan can protect you from very large coinsurance bills and extend coverage beyond Medicare’s standard limit.

2. Part A Hospice Care Coinsurance or Copayments

Medicare Part A covers hospice, but there may be small copayments or coinsurance for certain services and medications.

Most Medigap plans help pay these hospice-related out‑of‑pocket costs, reducing what you owe when you or a family member needs hospice care.

3. Skilled Nursing Facility (SNF) Care Coinsurance

If you need skilled nursing facility care after a hospital stay, Original Medicare covers a portion, but you may owe a daily coinsurance after a certain number of days.

Many Medigap plans cover this SNF coinsurance, although not all. Plans that do cover it can significantly reduce the cost of extended skilled nursing care for rehabilitation or recovery.

4. Part A Deductible

The Medicare Part A deductible is the amount you pay when you’re admitted to the hospital before Medicare starts paying its share. It is typically a per benefit period amount, not an annual one, so you may pay it more than once in a year if you have multiple hospital stays.

Most Medigap plans cover all or part of the Part A deductible, helping you avoid a large upfront bill if you’re hospitalized.

5. Part B Coinsurance or Copayments

Medicare Part B covers outpatient care, doctor visits, and many services outside the hospital. Usually, once you meet the Part B deductible, you pay 20% coinsurance of the Medicare-approved amount for covered services.

Most Medigap plans pay some or all of that 20%, which can make a substantial difference over a year of doctor visits, tests, and treatments.

• Many plans cover this coinsurance at 100%
• Some plans (such as certain cost-sharing types) cover only a portion and require you to pay some of each visit cost

6. Part B Excess Charges (In Some Plans)

Some doctors accept Medicare but do not accept Medicare’s “assignment” (the standard approved payment amount). In those cases, they may legally charge up to 15% above the Medicare-approved amount, depending on state rules. That extra amount is called a Part B excess charge.

Certain Medigap plans (most notably Plan F and Plan G) cover 100% of Part B excess charges, so you don’t pay that extra 15%. Other plans do not cover these excess charges, meaning you’re responsible for them if they apply.

7. Foreign Travel Emergency Care (Limited)

Original Medicare generally does not cover medical care outside the U.S., with a few narrow exceptions.

Some Medigap plans include limited foreign travel emergency coverage. While details vary by plan:

• Coverage is usually limited to emergency care only
• There is typically a lifetime maximum benefit
• A deductible and coinsurance may apply

This is not full international health insurance, but it can offer a layer of protection for unexpected emergencies while traveling abroad.

At-a-Glance: What Medigap Plans Commonly Cover

The exact details differ by standardized plan type, but the main categories of costs Medigap helps with can be summarized like this:

For any individual plan, it’s important to review its standardized benefits to see exactly which of these cost areas it covers.

What Medigap Plans Do NOT Cover

Understanding what Medigap does not cover is just as important as knowing what it does.

1. No Coverage for Services Not Covered by Original Medicare

Medigap only helps pay Medicare-approved costs. If a service is not covered by Original Medicare, Medigap will generally not cover it either. This often includes:

• Routine dental care (cleanings, fillings, dentures)
• Routine vision care (eyeglasses, contact lenses, routine eye exams)
• Routine hearing care (hearing aids and most related services)
• Routine foot care (with some medical exceptions)
• Cosmetic procedures not considered medically necessary

If you need coverage in these areas, people often look at separate stand‑alone plans or discount programs, not Medigap.

2. No Coverage for Prescription Drugs (Part D)

Modern Medigap plans do not cover outpatient prescription drugs. Prescription coverage is handled through Medicare Part D drug plans, which you enroll in separately.

Some individuals who enrolled in Medigap plans many years ago may have older policies with limited drug coverage, but these are not typical for new enrollees and are not the standard today.

3. Not a Substitute for Medicare Advantage or Other Programs

Medigap is designed to pair with Original Medicare, not with:

• Medicare Advantage (Part C) plans
• Tricare, Veterans Affairs (VA) benefits, or other separate programs (each has its own rules about coordination)

If you enroll in a Medicare Advantage plan, you generally cannot keep or use a Medigap plan for those Advantage plan costs.

4. No Long-Term Custodial Care Coverage

Medigap plans do not cover long-term custodial care, such as:

• Help with daily activities in a nursing home over the long term
• Assisted living facility costs
• In‑home custodial care if it’s not considered skilled medical care

These types of services are usually outside the coverage of both Original Medicare and Medigap and may require separate planning, private payment, or other programs depending on eligibility.

How Medigap Coverage Differs by Plan Type

Medigap plans are standardized, meaning each plan letter (like Plan G or Plan N) offers the same basic benefits no matter which insurance company sells it in a given state.

However, each plan letter covers a different combination of benefits and cost-sharing.

Common Ways Plans Differ

Medigap plans can vary in:

• Whether they cover the Part B deductible
• How much of the Part A deductible they cover
• Whether they cover Part B excess charges
• Whether they include foreign travel emergency coverage
• Whether they use cost-sharing (you pay a percentage) versus full coverage

Additionally, certain plans (like Plan K and Plan L) use a cost-sharing model and include an annual out‑of‑pocket limit, after which the plan pays 100% of covered costs for the rest of the year.

How Medigap Works with Your Medicare Coverage

To understand what Medigap actually covers for you, it helps to see how the pieces interact.

Step-by-Step: A Typical Covered Service

1. You receive a service that is covered by Original Medicare (for example, a doctor visit).
2. Medicare pays its share (after any applicable deductibles are met).
3. Medigap looks at the remaining approved amount, such as the Part B coinsurance or Part A deductible.
4. Your Medigap plan pays its portion of those remaining costs, based on the benefits of your plan letter.
5. You pay anything left over, such as deductibles or copays that your Medigap plan does not cover.

The key point:
Medigap does not change what Medicare covers; it changes what you pay out-of-pocket for those Medicare-covered services.

When Medigap Coverage Starts and How It’s Maintained

Coverage rules and timing can influence what your Medigap plan covers and how easily you can get it.

Guaranteed-Issue Windows and Medical Underwriting

• During your Medigap Open Enrollment Period (typically the 6 months starting when you’re both 65 or older and enrolled in Part B), insurance companies usually must:

  • Offer any Medigap plan they sell in your area
  • Cover you without medical underwriting (no higher charges or denials based solely on health)

• Outside of certain protected times, companies may:

  • Use medical underwriting
  • Potentially charge more or decline your application based on health conditions, depending on state rules

This doesn’t change what the plan covers, but it can influence which plan letter you can access and at what cost.

Common Consumer Experiences with Medigap Coverage

People who choose Medigap often do so for reasons such as:

• Predictable costs for doctor visits and hospital stays
• Reduced worry about large medical bills from a long hospital stay or serious illness
• Simpler billing, since providers bill Medicare first and then Medigap

Others may decide Medigap is not right for them if they:

• Prefer the network-based structure and additional extras sometimes offered by Medicare Advantage (understanding it works differently)
• Are comfortable with paying more out-of-pocket in exchange for lower monthly premiums elsewhere

The right choice varies by person, but understanding what Medigap covers is central to making an informed decision.

Quick Recap: Key Takeaways About Medigap Coverage

Medigap plans generally DO cover:

• ✅ Part A hospital coinsurance and up to 365 extra hospital days
• ✅ Part A hospice coinsurance/copayments
• ✅ Some or all Skilled Nursing Facility coinsurance (depending on plan)
• ✅ Part A deductible (fully or partially, depending on plan)
• ✅ Part B coinsurance and copayments (often 100% for many services)
• ✅ Part B excess charges (in certain plan letters only)
• ✅ Limited foreign travel emergency care (for specific plans)

Medigap plans generally do NOT cover:

• ❌ Services that Medicare itself does not cover, such as routine dental, vision, and hearing
• ❌ Prescription drugs (you typically need a separate Part D plan)
• ❌ Long-term custodial care in nursing homes or assisted living
• ❌ Eyeglasses, hearing aids, or most dental work (unless covered by Medicare in specific medical situations)
• ❌ Costs related to Medicare Advantage plans, since Medigap works with Original Medicare only

Understanding exactly what Medigap plans cover helps you evaluate whether a Medicare Supplement policy fits your needs and how it might reduce your out-of-pocket expenses for Medicare-covered services. Reviewing the benefits of specific Medigap plan letters and comparing them to your expected healthcare use can give you a clearer picture of which coverage approach aligns best with your situation.