Medigap Plans Explained: How to Choose the Best Medicare Supplement

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If you’ve been researching Medicare, you’ve almost certainly come across the term Medigap plans — and you probably have questions. What exactly are they? How many types are there? What do they cost? And most importantly, which one is best for you? You’re not alone in feeling overwhelmed. The Medigap system involves ten different plan letters, varying rules by state, and enrollment windows that can make or break your options. But here’s the good news: once you understand the basics, choosing the right Medicare Supplement plan is actually straightforward. This guide will explain every Medigap plan available in 2026, compare them side by side, and walk you through exactly how to choose the best one for your situation.

Key Takeaways

Medigap (Medicare Supplement) plans help cover the out-of-pocket costs that Original Medicare doesn’t pay — including deductibles, coinsurance, and copayments that can add up to thousands of dollars per year.
There are 10 standardized Medigap plan types (A, B, C, D, F, G, K, L, M, and N), and each one covers the same benefits regardless of which insurance company sells it — the only differences between carriers are price and service quality.
Plan G is the most popular Medigap plan for new enrollees in 2026, offering near-complete coverage at competitive premiums, while Plan N is the best budget-friendly alternative.
Your Medigap Open Enrollment Period is the most important enrollment window — during this 6-month period starting at age 65, you’re guaranteed acceptance regardless of health conditions and will get the best available rates.

What Is Medigap?

Medigap — officially called Medicare Supplement Insurance — is private health insurance designed to work alongside Original Medicare (Part A and Part B). It fills the “gaps” in Original Medicare’s coverage, which is exactly where it gets its name.

Here’s the basic framework:

Original Medicare covers about 80% of your approved medical costs. You’re responsible for the remaining 20%, plus various deductibles and coinsurance amounts. These out-of-pocket costs have no annual cap under Original Medicare, meaning a serious illness or extended hospital stay could cost you tens of thousands of dollars.

Medigap plans cover some or all of those remaining out-of-pocket costs. When you have a Medigap plan, the process works like this:

You receive medical care from any provider who accepts Medicare
Medicare pays its share (typically 80% of approved charges)
Your Medigap plan pays some or all of the remaining costs
You pay little to nothing out of pocket (depending on your plan)

Important Things to Know About Medigap

Medigap only works with Original Medicare — If you have a Medicare Advantage plan (Part C), you cannot use a Medigap plan. They don’t work together. You must choose one path or the other.
Medigap plans don’t include prescription drug coverage — You’ll need a separate Medicare Part D plan for your medications.
Medigap plans are individual policies — Each person needs their own plan. If both you and your spouse want Medigap coverage, you’ll each need separate policies.
You can see any doctor or hospital that accepts Medicare — Unlike Medicare Advantage plans, Medigap plans have no provider networks. If the doctor accepts Medicare, your Medigap plan works there. Period. This is true anywhere in the United States.
Medigap coverage is standardized by federal law — A Plan G from one company covers the exact same benefits as a Plan G from another company. The government defines what each plan letter covers. Companies can only compete on price and service — not on benefits.

All 10 Medigap Plans Explained

There are 10 standardized Medigap plan types, each identified by a letter. Here’s what each one covers:

Plan A — Basic Benefits Only

Plan A is the most basic Medigap plan. It covers:

Part A coinsurance and hospital costs (up to 365 additional days after Medicare benefits are exhausted)
Part B coinsurance or copayment
First three pints of blood
Part A hospice care coinsurance or copayment

Not covered: Part A deductible, Part B deductible, skilled nursing facility coinsurance, Part B excess charges, foreign travel emergencies.

Who it’s for: Plan A is rarely the best choice because its limited coverage combined with relatively modest premium savings doesn’t offer compelling value compared to Plan G or Plan N.

Plan B — Adds the Part A Deductible

Plan B covers everything Plan A covers, plus:

Part A deductible ($1,676 in 2026)

Who it’s for: Slightly better value than Plan A, but still leaves significant gaps. Not widely recommended.

Plan C — Comprehensive (Pre-2020 Only)

Plan C covers all basic benefits plus:

Part A deductible
Part B deductible
Skilled nursing facility coinsurance
Foreign travel emergency (80%)

Important: Plan C is only available to people who became eligible for Medicare before January 1, 2020. If you turned 65 after that date, you cannot enroll in Plan C.

Who it’s for: Similar to Plan F but without excess charge coverage. If you’re eligible and want comprehensive coverage, Plan F or Plan G is typically a better choice.

Plan D — Near-Comprehensive Without Part B Deductible

Plan D covers:

All basic benefits (Part A coinsurance, Part B coinsurance, blood, hospice)
Part A deductible
Skilled nursing facility coinsurance
Foreign travel emergency (80%)

Not covered: Part B deductible, Part B excess charges.

Who it’s for: Plan D is very similar to Plan G but without coverage for Part B excess charges. Since Plan G typically costs only slightly more and includes excess charge protection, Plan G is usually the better choice.

Plan F — The Most Comprehensive (Pre-2020 Only)

Plan F covers everything — it’s the only Medigap plan that covers all standardized benefits:

All basic benefits
Part A deductible
Part B deductible
Skilled nursing facility coinsurance
Part B excess charges
Foreign travel emergency (80%)

Important: Like Plan C, Plan F is only available to people who became eligible for Medicare before January 1, 2020.

Who it’s for: If you’re eligible and want zero out-of-pocket costs, Plan F delivers. However, Plan F premiums are significantly higher than Plan G — and the only additional benefit is coverage of the $257 Part B deductible. Most financial advisors recommend Plan G over Plan F because the premium savings far exceed the $257 you’d pay out of pocket.

Additionally, since no new enrollees are entering Plan F, its risk pool is aging, which means Plan F premiums are increasing faster than Plan G premiums over time.

Plan G — The Gold Standard for New Enrollees

Plan G covers:

All basic benefits
Part A deductible
Skilled nursing facility coinsurance
Part B excess charges
Foreign travel emergency (80%)

Not covered: Part B deductible ($257 in 2026)

Who it’s for: Plan G is the most popular Medigap plan in 2026 for good reason. It covers virtually everything except one small annual deductible. With premiums typically ranging from $100–$250 per month, it offers the best balance of comprehensive coverage and reasonable cost. This is the plan most Medicare experts recommend for new enrollees.

Plan K — 50% Cost-Sharing

Plan K is a cost-sharing plan that covers:

50% of Part A coinsurance (100% after out-of-pocket limit)
50% of Part B coinsurance
50% of blood costs
50% of Part A hospice coinsurance
50% of skilled nursing facility coinsurance
Part A deductible: 50%
Annual out-of-pocket limit: $7,060 in 2026 (after reaching this, the plan covers 100%)

Who it’s for: Seniors on a tighter budget who want some protection against catastrophic costs. The lower premiums come at the cost of significant cost-sharing on routine care.

Plan L — 75% Cost-Sharing

Plan L is similar to Plan K but with better coverage:

75% of most covered benefits (instead of 50%)
Annual out-of-pocket limit: $3,530 in 2026

Who it’s for: A middle ground between Plan K’s minimal coverage and the full coverage plans. Still not as popular as Plan G or Plan N for most beneficiaries.

Plan M — Covers Half the Part A Deductible

Plan M covers:

All basic benefits
50% of Part A deductible
Skilled nursing facility coinsurance
Foreign travel emergency (80%)

Not covered: Part B deductible, Part B excess charges, 50% of Part A deductible.

Who it’s for: Plan M is rarely sold and not widely available. The premium savings over Plan G are usually too small to justify the gaps in coverage.

Plan N — The Budget-Friendly Choice

Plan N covers:

All basic benefits (with copays — see below)
Part A deductible
Skilled nursing facility coinsurance
Foreign travel emergency (80%)

Cost-sharing:

Up to $20 copay for some office visits
Up to $50 copay for ER visits that don’t result in hospital admission
Part B excess charges are not covered

Not covered: Part B deductible, Part B excess charges.

Who it’s for: Plan N is the second most popular Medigap plan and the best option for seniors who want good coverage at a lower premium. Premiums are typically $20–$50 less per month than Plan G. If you’re generally healthy and don’t mind occasional small copays, Plan N can save you hundreds of dollars per year.

Medigap Plan Comparison Table

Here’s a side-by-side comparison of all 10 Medigap plans and what they cover:

| Benefit | A | B | C* | D | F* | G | K | L | M | N | |———|—|—|—-|—-|—-|—-|—|—|—|—| | Part A coinsurance & hospital (365 days) | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | 50% | 75% | ✅ | ✅ | | Part B coinsurance/copay | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | 50% | 75% | ✅ | ✅ (copays apply) | | Blood (first 3 pints) | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | 50% | 75% | ✅ | ✅ | | Part A hospice coinsurance | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ | 50% | 75% | ✅ | ✅ | | Part A deductible | ❌ | ✅ | ✅ | ✅ | ✅ | ✅ | 50% | 75% | 50% | ✅ | | Part B deductible | ❌ | ❌ | ✅ | ❌ | ✅ | ❌ | ❌ | ❌ | ❌ | ❌ | | Part B excess charges | ❌ | ❌ | ❌ | ❌ | ✅ | ✅ | ❌ | ❌ | ❌ | ❌ | | Skilled nursing coinsurance | ❌ | ❌ | ✅ | ✅ | ✅ | ✅ | 50% | 75% | ✅ | ✅ | | Foreign travel emergency | ❌ | ❌ | ✅ | ✅ | ✅ | ✅ | ❌ | ❌ | ✅ | ✅ | | Out-of-pocket limit | — | — | — | — | — | — | $7,060 | $3,530 | — | — |

Plans C and F are only available to those eligible for Medicare before January 1, 2020.

How Much Do Medigap Plans Cost in 2026?

Medigap premiums vary based on your age, location, gender, tobacco use, and the insurance company you choose. Here are approximate monthly premium ranges for the most popular plans (65-year-old, national averages):

| Plan | Monthly Premium Range | Annual Cost Range | |——|———————-|——————-| | Plan A | $75–$175 | $900–$2,100 | | Plan B | $100–$200 | $1,200–$2,400 | | Plan F* | $150–$300 | $1,800–$3,600 | | Plan G | $100–$250 | $1,200–$3,000 | | Plan K | $40–$100 | $480–$1,200 | | Plan L | $60–$140 | $720–$1,680 | | Plan N | $80–$200 | $960–$2,400 |

Plan F available only to pre-2020 Medicare eligibles.

How Insurance Companies Set Medigap Premiums

Insurance companies use one of three pricing methods for Medigap plans:

Community-rated (no-age-rated): Everyone pays the same premium regardless of age. States like New York require this method. Your premium won’t increase just because you get older (though it may increase due to inflation or other factors).

Issue-age-rated: Your premium is based on your age when you first buy the plan. It won’t increase due to aging, but it may increase due to inflation. Buying younger locks in a lower base rate.

Attained-age-rated: Your premium is based on your current age and increases as you get older. This is the most common method. Premiums start lower but grow over time.

Understanding your state’s pricing rules and each company’s pricing method is important for projecting your long-term costs.

The Medigap Open Enrollment Period

The single most important thing to understand about Medigap enrollment is your Open Enrollment Period (OEP). This window provides crucial protections that you won’t have at any other time.

When Is Your OEP?

Your Medigap OEP is a 6-month window that begins on the first day of the month you:

Are age 65 or older, AND
Are enrolled in Medicare Part B

For most people, this means the OEP starts the month they turn 65 (assuming they enroll in Part B at the same time). If you delay Part B enrollment, your OEP starts when Part B kicks in.

Why the OEP Matters So Much

During your OEP:

Guaranteed acceptance: Insurance companies must sell you any Medigap plan they offer, regardless of your health. You could have diabetes, heart disease, cancer history — it doesn’t matter. They have to accept you.
No health-based pricing: Companies cannot charge you more because of pre-existing conditions.
No waiting periods: Coverage for pre-existing conditions begins immediately.
Full plan selection: You can choose any plan letter available in your state.

What Happens After the OEP?

Once your 6-month OEP closes, insurance companies can use medical underwriting to evaluate your application. This means they can:

Deny your application based on health conditions
Charge significantly higher premiums
Impose waiting periods before covering pre-existing conditions
Limit which plans they’ll offer you

This is why the OEP is so critical. If you’re in poor health, buying Medigap outside the OEP may be extremely difficult or expensive. Even if you’re healthy, you’ll likely pay more than you would have during the OEP.

Bottom line: If you’re approaching 65 and planning to use Original Medicare, start shopping for Medigap plans 2–3 months before your OEP begins. Don’t wait until the last minute.

Guaranteed Issue Rights

Even outside the OEP, there are specific situations where federal law gives you a guaranteed issue right to buy a Medigap plan without medical underwriting. These situations include:

Your Medicare Advantage plan leaves your area or stops offering coverage, and you want to switch to Original Medicare + Medigap
You lose employer or union group health coverage that supplemented Medicare
Your Medigap insurance company goes bankrupt or otherwise stops your coverage through no fault of your own
You were misled by the insurance company into dropping your Medigap plan
You tried Medicare Advantage for the first time when you turned 65 and want to switch back to Original Medicare within 12 months (this is called the “trial right”)
You dropped a Medigap plan to join a Medicare Advantage plan for the first time and want to go back within 12 months (also a trial right)

When you have a guaranteed issue right, you typically have 63 days to apply for a Medigap plan. During this window, insurance companies must accept you at standard rates regardless of health.

State Variations in Medigap

While Medigap plans are standardized at the federal level, three states have their own unique systems:

Massachusetts

Massachusetts uses its own set of Medigap plan names (Core, Supplement 1, and Supplement 1A) instead of the standard letter system. The benefits are slightly different from the federal standardized plans.

Minnesota

Minnesota has its own Medigap standardization system with a basic plan and optional riders. Plans are structured differently from the federal system, though they serve the same purpose.

Wisconsin

Wisconsin uses a modular approach where you buy a basic plan and can add riders for additional coverage. Like Massachusetts and Minnesota, their system is state-specific.

If you live in one of these three states, your Medigap options will look different from what’s described in the federal standardized plan chart above. Work with a local insurance broker who understands your state’s specific Medigap rules.

Other State-Specific Considerations

Even in states that follow the federal standardization:

Some states guarantee Medigap access year-round (e.g., Connecticut, Maine, Massachusetts, New York) — not just during the OEP
Some states prohibit gender-based pricing
Some states require “community rating,” meaning premiums can’t increase due to age
Plan availability varies by state — not every plan letter is offered everywhere

Check with your state’s Department of Insurance or an independent broker to understand your state’s specific rules.

How to Choose the Best Medigap Plan for You

With 10 plan options (and many insurance companies offering each one), how do you narrow down your choice? Here’s a practical step-by-step approach:

Step 1: Decide How Much Risk You Want to Take

Medigap plans fall on a spectrum from maximum coverage to maximum savings:

Maximum coverage, higher premiums: Plan G (or Plan F if you’re eligible)
Good coverage, moderate premiums: Plan N
Partial coverage, lowest premiums: Plan K or Plan L
Everything else: Plans A, B, D, and M fall somewhere in between but are rarely the best choice for most people

For most new Medicare beneficiaries, the real choice comes down to Plan G vs. Plan N.

Step 2: Plan G vs. Plan N — The Key Decision

Choose Plan G if:

You see doctors frequently
You want maximum predictability in your healthcare costs
You don’t want to think about copays or excess charges
You value simplicity and peace of mind
You can comfortably afford the premium

Choose Plan N if:

You’re generally healthy and don’t visit doctors often
You want to save $20–$50 per month on premiums
You don’t mind occasional $20 copays for office visits
You live in a state that limits or prohibits excess charges (making that coverage gap irrelevant)
You’re budget-conscious and willing to accept small, predictable copays

Step 3: Compare Insurance Companies

Once you’ve chosen your plan letter, compare quotes from multiple insurance companies. Remember: the benefits are identical across carriers, so you’re comparing:

Price — Get quotes from at least 3–5 companies
Financial stability — Check AM Best ratings to ensure the company can pay claims long-term
Customer service — Read reviews and check complaint ratios through the NAIC
Rate increase history — Some companies raise rates more aggressively than others over time

Step 4: Work with an Independent Broker

An independent Medicare insurance broker is one of the most valuable resources available to you — and their services are free. Unlike a captive agent who works for one company, an independent broker can:

Compare all available Medigap plans and carriers in your area
Show you the exact premiums for your age, gender, and ZIP code
Help you understand the differences between plans
Assist with the enrollment process
Provide ongoing support if you have questions or issues later

They’re paid commissions by the insurance companies, not by you, so there’s no cost for their expertise.

Step 5: Enroll During Your Open Enrollment Period

Time your enrollment to fall within your 6-month Medigap OEP whenever possible. This guarantees acceptance and the best available rates. Start shopping 2–3 months before your OEP begins so you’re ready to enroll on day one.

Medigap vs. Medicare Advantage: Which Path Is Right?

Before choosing a specific Medigap plan, you need to make the fundamental decision: do you want Original Medicare + Medigap, or do you want a Medicare Advantage plan?

Here’s a quick comparison:

Neither choice is universally better — it depends on your health, budget, lifestyle, and priorities. But if you value the ability to see any doctor without restrictions and want predictable, minimal out-of-pocket costs, Original Medicare with a Medigap plan is hard to beat.

Final Thoughts

Medigap plans exist for one reason: to protect you from the financial gaps in Original Medicare. Understanding your options doesn’t have to be complicated. Here’s the short version:

Plan G is the best all-around Medigap plan for most new enrollees in 2026 — comprehensive coverage, predictable costs, and competitive premiums.
Plan N is the smart budget alternative — slightly less coverage, but meaningful premium savings.
Enroll during your Open Enrollment Period — this is non-negotiable for getting the best deal and guaranteed acceptance.
Compare multiple insurance companies — identical benefits mean the only differences are price and service.
Work with an independent broker — free expert help that can save you hundreds or thousands of dollars.

Your health coverage is too important to leave to chance or brand recognition alone. Take the time to understand your Medigap options, compare your choices, and choose the plan that gives you the coverage and peace of mind you deserve.