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Coverage · Medigap supplement

Medigap supplement plans, compared.

Ten standardized plans, lettered A through N. The benefits within each letter are identical across every insurance company that sells them. The only thing that varies is price. This page compares all ten side by side, with deep-dives on each.

Side-by-side comparison

All ten plans, at a glance

The benefits below are federally standardized. Plan G from one carrier covers exactly what Plan G from another carrier covers. Premiums vary widely, but coverage does not. Scroll horizontally on mobile to see all plan letters.

BenefitPlan APlan BPlan Cpre-2020 onlyPlan DPlan Fpre-2020 onlyPlan GPlan KPlan LPlan MPlan N
Part A hospital coinsurance & 365 extra days●●●●●●●●●●
Part B coinsurance or copayment●●●●●●◐◕●●*
Blood (first 3 pints)●●●●●●◐◕●●
Part A hospice coinsurance/copayment●●●●●●◐◕●●
Skilled nursing facility coinsurance○○●●●●◐◕●●
Part A deductible○●●●●●◐◕◐●
Part B deductible○○●○●○○○○○
Part B excess charges○○○○●●○○○○
Foreign travel emergency○○●●●●○○●●
Out-of-pocket limit (2026)------$8,000$4,000--
High-deductible option----$2,950$2,950----
● Full coverage (100%)
◕ 75% coverage
◐ 50% coverage
○ Not covered
●* Conditional (small copays apply)

Plan N copays: Up to $20 for some office visits and up to $50 for ER visits that do not result in inpatient admission.

Plans C and F: Available only to those who became eligible for Medicare before January 1, 2020. Closed to newer enrollees.

High-deductible variants: Plans F and G offer high-deductible options ($2,950 in 2026). You pay all Medicare-covered costs up to the deductible, then the plan pays 100%.

Plans K and L: Once you reach the out-of-pocket limit ($8,000 for K, $4,000 for L in 2026) plus the Part B deductible, the plan pays 100% for the rest of the calendar year.

One letter at a time

Each plan, explained

The summary table shows what each plan covers. These cards explain who each plan is best for, what it actually means in practice, and the trade-offs to weigh.

Plan A
The basic floor
Best for
Younger, healthy beneficiaries who want bare-minimum protection.
Covers
Part A hospital coinsurance, Part B coinsurance, blood (first 3 pints), Part A hospice coinsurance.
Gaps
Part A deductible ($1,736 in 2026), Part B deductible ($283), SNF coinsurance ($217/day after day 20), foreign travel emergency.
Required to be offered by every Medigap insurer. The cheapest standardized plan but leaves the largest gaps.
Plan B
Plan A plus the Part A deductible
Best for
Beneficiaries who want hospital deductible coverage but lower premiums than Plan G.
Covers
Everything Plan A covers, plus the Part A deductible ($1,736 in 2026).
Gaps
Part B deductible, SNF coinsurance, Part B excess charges, foreign travel.
Less common than Plan G. Worth comparing premium to Plan G - the additional benefits in G often justify a small premium difference.
Plan C
The legacy comprehensive plan
Pre-2020 eligible only
Best for
Pre-2020 eligible beneficiaries who want comprehensive coverage including the Part B deductible.
Covers
Plans A and B benefits, plus SNF coinsurance, Part B deductible, foreign travel emergency.
Gaps
Part B excess charges only.
Not available to anyone newly eligible for Medicare on or after January 1, 2020. Existing Plan C policyholders can keep coverage. Premiums tend to rise faster than Plan D as the closed risk pool ages.
Plan D
Comprehensive without Part B deductible coverage
Best for
Beneficiaries who want most Plan G benefits but at a slightly lower premium and do not need excess charge coverage.
Covers
Plans A, B benefits plus SNF coinsurance and foreign travel.
Gaps
Part B deductible, Part B excess charges.
Similar to Plan G except Plan D does not cover Part B excess charges. Most physicians accept Medicare assignment, so excess charges are rare in practice.
Plan F
The legacy 100% plan
Pre-2020 eligible only
Best for
Pre-2020 eligible beneficiaries who want zero out-of-pocket costs for Medicare-covered services.
Covers
Every standardized benefit: hospital, medical, blood, hospice, SNF, both deductibles, excess charges, foreign travel.
Gaps
None among Medicare-covered services. Drugs require separate Part D.
Not available to anyone newly eligible for Medicare on or after January 1, 2020. The closed risk pool means premiums rise faster than other plans. Many existing Plan F policyholders are switching to Plan G to escape rising premiums.
Plan G
The most popular plan for new enrollees
Best for
Most new Medicare beneficiaries (post-2020). The successor to Plan F.
Covers
Everything except the Part B deductible. Includes Part B excess charges and foreign travel emergency.
Gaps
Part B deductible ($283 in 2026) is your only meaningful out-of-pocket exposure beyond your premium.
Plan G covers about 39% of all Medigap enrollees. After paying $283, your medical costs are essentially capped for the year. Predictable. Comprehensive. The default recommendation for most new enrollees.
Plan K
Lower premium, cost-sharing structure
Best for
Beneficiaries who want lower monthly premiums and can absorb cost-sharing up to a defined annual limit.
Covers
Part A hospital coinsurance fully. 50% of most other benefits (Part B coinsurance, blood, hospice, SNF, Part A deductible).
Gaps
No Part B deductible coverage. No excess charges. No foreign travel.
Out-of-pocket limit: $8,000 in 2026. Once you reach that limit, the plan pays 100% for the rest of the calendar year. Useful if you have meaningful savings to absorb cost-sharing.
Plan L
Middle ground between K and full plans
Best for
Beneficiaries who want lower premiums than Plan G but more coverage than Plan K.
Covers
Part A hospital coinsurance fully. 75% of most other benefits.
Gaps
No Part B deductible coverage. No excess charges. No foreign travel.
Out-of-pocket limit: $4,000 in 2026 (half of Plan K). Once reached, plan pays 100% for rest of year. Less common than K, G, or N.
Plan M
Hybrid with partial Part A deductible
Best for
Niche option for beneficiaries wanting most benefits but willing to pay half the Part A deductible.
Covers
Plans A, B benefits plus SNF coinsurance, foreign travel, and 50% of Part A deductible.
Gaps
Part B deductible. Part B excess charges. Half of Part A deductible.
Limited carrier support. Often unavailable in many states. Premiums can be similar to Plan G with worse benefits.
Plan N
Lower premium with small copays
Best for
Beneficiaries comfortable with copays in exchange for lower monthly premium than Plan G.
Covers
Hospital, medical, blood, hospice, SNF, Part A deductible, foreign travel.
Gaps
Part B deductible. Part B excess charges. Up to $20 copay for some office visits and up to $50 for ER visits not resulting in admission.
Plan N covers about 10% of Medigap enrollees. Premium is typically $30-60/month less than Plan G. Whether the savings outweigh the copays depends on how often you see doctors and whether your physicians accept Medicare assignment.
What you need to know

The core mechanics

Beyond the plan-by-plan benefits, a few principles shape every Medigap decision. The enrollment window, the rating method, and how state rules affect availability.

The six-month open enrollment window

Your Medigap Open Enrollment Period starts the month your Part B becomes effective and you are 65 or older. It lasts six months. During this window, every Medigap insurer must accept you regardless of health, charge you the same as a healthy applicant, and impose no waiting periods.

Outside this window, insurers can require medical underwriting - asking health questions, denying you, or charging more. Your choices narrow significantly.

Use this window. It is the single most important moment in Medigap. Once it closes, getting the plan you want at a fair price gets harder.

How premiums are rated

Community-rated: Same premium for everyone with the policy regardless of age. Premiums increase only due to inflation. Most predictable long-term.

Issue-age: Premium based on your age when you first bought the policy. Never increases due to age, only inflation. Predictable.

Attained-age: Premium increases as you age. Cheapest at 65, most expensive at 80+. Many Plan G policies use this method.

Ask the insurer which rating method applies. Two policies with the same letter and same premium today can cost very different amounts at age 80.

Different rules for three states

Massachusetts, Minnesota, and Wisconsin have their own standardized Medigap structures that pre-date the federal A-N system. The benefits are similar but organized differently.

Massachusetts: Core and Supplement 1 plans. Minnesota: Basic and Extended Basic plans with optional riders. Wisconsin: Basic plan with optional riders.

If you live in one of these states, the federal comparison logic still applies but the specific plan names and benefit organization differ. Check with your state insurance department or your state SHIP.

What Medigap does not cover

Medigap covers the gaps in Original Medicare. It does not cover prescription drugs (you need a separate Part D plan), dental, vision, hearing aids, long-term care, or services Original Medicare itself does not cover.

Medigap does not work with Medicare Advantage. The two are mutually exclusive. Choosing Advantage means giving up Medigap eligibility for as long as you stay in MA.

Plan for the full picture: Medigap + Part D + dental/vision/hearing if needed. Total monthly cost is usually $200-400 depending on plans chosen.

Switching plans after enrollment

You can switch Medigap plans at any time, but underwriting applies after your initial six-month window. The new insurer can ask health questions, deny coverage, charge higher premiums, or impose waiting periods for pre-existing conditions.

Some states have additional protections that allow easier switching - California, Connecticut, Maine, Massachusetts, Missouri, New York, Oregon, and Washington offer broader rights. Outside those states, switching is risky if your health changed since initial enrollment.

The guaranteed issue exceptions

A few situations restore your guaranteed-issue rights even after the initial window closes. Your Medicare Advantage plan terminates its contract or stops serving your area. You move out of your MA plan's service area. Your employer retiree health coverage ends. Your Medigap insurer goes bankrupt.

In these specific situations, certain Medigap plans must accept you within 63 days of the qualifying event. Document the trigger event and act quickly.
Common questions

Questions people ask all the time

Cross-cutting questions about Medigap that come up across plan letters. Tap any question to see the answer.

I just turned 65 and signed up for Original Medicare. When can I get Medigap?
Your Medigap Open Enrollment Period starts the month your Part B becomes effective and lasts six months. During this window, no insurer can deny you, charge more for health reasons, or impose waiting periods. Outside this window, underwriting applies and insurers can refuse you. This is the single most important window in Medigap enrollment - use it.
Why is Plan G the most popular plan?
Plan G covers everything Original Medicare doesn't, except the annual Part B deductible ($283 in 2026). After paying that one deductible, your Medicare-covered medical costs are essentially capped for the rest of the year. It replaced Plan F as the default for new enrollees because Plan F was eliminated for those newly eligible in 2020. About 39% of all Medigap enrollees have Plan G.
What's the difference between Plan G and Plan N?
Both cover most major Medicare gaps. Plan N has lower monthly premium but charges copays - up to $20 for some office visits and up to $50 for ER visits that don't result in admission. Plan N also doesn't cover Part B excess charges. If you see doctors frequently or care about predictability, Plan G. If you see doctors rarely and want lower premium, Plan N. The break-even is usually 5-8 office visits per year.
Why are Plans C and F not available?
The Medicare Access and CHIP Reauthorization Act of 2015 eliminated coverage of the Part B deductible for new Medigap policies sold to people newly eligible for Medicare on or after January 1, 2020. Plans C and F covered that deductible, so they were closed to new enrollees. If you became Medicare-eligible before 2020, you can still buy or keep these plans. Premiums are rising faster as the closed risk pool ages.
Are all Plan G policies the same?
Benefits are identical by federal law - Plan G from any insurer covers the same services in the same amounts. What differs is premium, financial stability of the insurer, and customer service. The same Plan G can range from $90 to $250 per month depending on insurer, location, and how the insurer rates premiums (community-rated, issue-age, attained-age). Comparing quotes matters.
What's the difference between community-rated, issue-age, and attained-age pricing?
Community-rated: same premium for everyone with that policy, regardless of age. Premiums increase only due to inflation. Issue-age: premium based on your age when you first bought the policy and never increases due to age. Attained-age: premium increases as you get older. Attained-age is cheapest at 65 but most expensive at 80. Issue-age and community-rated are more predictable long-term.
Can I switch Medigap plans later?
Technically yes, but underwriting applies after your initial six-month window. The new insurer can ask health questions, deny you, or charge more for pre-existing conditions. Some states have additional protections - California, Connecticut, Maine, Massachusetts, Missouri, New York, Oregon, and Washington offer broader switching rights. Outside those states, switching is risky if your health has changed since your initial enrollment.
Does Medigap work with Medicare Advantage?
No. The two are mutually exclusive. If you have Medicare Advantage, you cannot buy or use a Medigap policy. If you switch from Advantage back to Original Medicare later, you may have limited Medigap rights and could be denied or charged more based on health. The Medigap window is one-time except in specific guaranteed-issue situations.
Do I still need Part D if I have Medigap?
Yes. Medigap does not cover prescription drugs (modern Medigap policies sold since 2006). You need a separate Part D plan or face the late enrollment penalty. The Medigap + Part D + Original Medicare combination is the traditional Medicare structure most people use when they choose Original over Advantage.
My state has different Medigap rules. What do I need to know?
Massachusetts, Minnesota, and Wisconsin have their own standardized Medigap formats different from the federal A-N letters. The benefits are similar but structured differently. If you live in one of those states, the comparison logic above applies but the specific plan names and structure differ. Check with your state insurance department or your state SHIP for state-specific guidance.
Data sources & methodology
Federal regulations and standards
Medicare Supplement Insurance standardization (Social Security Act Section 1882). Standardized plan benefits (NAIC Medicare Supplement Insurance Minimum Standards Model Regulation). Medigap eligibility for Plans C and F restriction (Medicare Access and CHIP Reauthorization Act of 2015, Section 401). Six-month Open Enrollment Period (42 USC 1395ss). Guaranteed issue rights (42 CFR 411.107). State-specific variations recognized for Massachusetts, Minnesota, and Wisconsin (federal waiver authority).
2026 figures verified
Plan K out-of-pocket limit $8,000 · Plan L out-of-pocket limit $4,000 · High-deductible Plans F and G deductible $2,950 · Part B deductible (covered by C, F) $283 · Part A deductible (covered by B, C, D, F, G, M-50%, N) $1,736 · SNF coinsurance $217/day. All per CMS 2026 Medicare Supplement standardized benefit chart and Medicare.gov compare benefits page.
Free help comparing Medigap plans: State Health Insurance Assistance Program / SHIP (1-877-839-2675, shiphelp.org) for free unbiased counseling - SHIP counselors do not sell insurance · Your state insurance department for state-specific rules and complaints · Medicare.gov compare benefits tool for the official federal benefit chart · 1-800-MEDICARE for general guidance.
This page provides general guidance only and is not legal, financial, or insurance advice. Medigap premiums and availability vary by carrier, state, and individual circumstances. Get quotes from multiple carriers before deciding. Last updated April 2026. If you believe any information is inaccurate, let us know.