Medicare Supplement (Medigap) Complete Guide 2026

Original Medicare is great. It covers a lot. But here's what the Medicare welcome packet buries in small print: it doesn't cover everything. Not even close.

Medicare Part A covers hospital stays — but you're on the hook for a $1,736 deductible every benefit period. Part B covers doctor visits and outpatient care — but only 80% of approved costs. That other 20%? Yours. With no annual cap. None. If you have a major surgery and the bills run $200,000, your 20% share is $40,000. That's not a theoretical number — it's what Original Medicare actually exposes you to.

That gap is exactly what Medigap fills.

Medigap (short for Medicare Supplement Insurance) is a private insurance policy you buy on top of Original Medicare. It steps in and covers some or all of the cost-sharing that Medicare leaves behind — the deductibles, the coinsurance, the copays. You keep your red-white-and-blue Medicare card. You still use it everywhere Medicare is accepted. Medigap just acts like a second layer of insurance that catches what Medicare drops.

Here's the thing most people don't realize going in: Medigap is standardized. That means if you buy a Plan G from Mutual of Omaha or Plan G from AARP/UnitedHealthcare — the benefits are literally identical. Same coverage. Same rules. The only thing different is the premium and the company you're writing the check to. That standardization is actually huge for consumers because it turns Medigap shopping into a pure price comparison instead of a coverage puzzle.

But — and this matters — Medigap only works with Original Medicare (Parts A and B). It does not work with Medicare Advantage (Part C). If you're on Advantage, you can't layer a Medigap policy on top of it. Different system, different rules. We'll get into the comparison later.

One more thing to lock in up front: Medigap does NOT include drug coverage. You need a separate Part D plan for prescriptions. Medigap handles the medical cost-sharing side only.

So the basic stack looks like this — Original Medicare handles the primary coverage, Medigap handles the gaps in that coverage, and a standalone Part D plan handles your drugs. Three separate pieces that work together. That's the framework everything else in this guide builds on.

There are ten standardized Medigap plan letters: A, B, C, D, F, G, K, L, M, and N. (Plans E, H, I, and J used to exist but were discontinued.) Each letter has a defined set of benefits that every insurer must offer identically.

Here's a plain-English breakdown of what each one actually covers:

**Plan A** — The bare minimum. Covers Part B coinsurance, hospital costs up to an additional 365 days after Medicare benefits are exhausted, blood (first 3 pints), and Part B preventive care coinsurance. That's it. No Part A deductible coverage, no skilled nursing facility coinsurance. Premiums are lowest but so is protection.

**Plan B** — Everything in Plan A, plus the Part A hospital deductible ($1,736 in 2026). A meaningful upgrade from A. Still doesn't cover skilled nursing coinsurance or excess charges.

**Plan C** — Covers almost everything: Part A deductible, Part B deductible ($283 in 2026), skilled nursing facility coinsurance, Part B excess charges are NOT covered, but foreign travel emergency coverage (80%) is included. Catch: only available if you were eligible for Medicare before January 1, 2020.

**Plan D** — Similar to C but doesn't cover the Part B deductible. Does cover skilled nursing coinsurance and foreign travel emergency. Also restricted in some states.

**Plan F** — The old king. Covered literally everything including the Part B deductible — no out-of-pocket costs whatsoever under Original Medicare. But Congress killed it for new enrollees. You can only buy Plan F if you were eligible for Medicare before January 1, 2020. If you already have it, keep it. But if you're enrolling now, Plan F is off the table.

**Plan G** — The current gold standard. Covers everything Plan F covers except the Part B deductible. So your only annual out-of-pocket is $283. After that, Plan G covers 100% of everything else. Most popular plan in America right now. We'll dig deep into this one.

**Plan K** — A cost-sharing plan. Covers 50% of most benefits instead of 100%. Has an annual out-of-pocket maximum of $8,000 in 2026. After you hit the max, it pays 100%. Lowest premiums of any comprehensive plan, but you're absorbing a lot more risk.

**Plan L** — Like K but covers 75% of benefits instead of 50%. Out-of-pocket max is $4,000 in 2026. Middle ground between K and the full-coverage plans.

**Plan M** — Covers 50% of the Part A deductible instead of 100%. Covers skilled nursing, foreign travel emergency, but not Part B excess charges or the Part B deductible. Lower premiums but more exposure on hospitalizations.

**Plan N** — A popular alternative to Plan G. Covers everything G covers except: you pay up to $20 copay for some office visits, up to $50 copay for ER visits (waived if admitted), and it doesn't cover Part B excess charges. Premiums run $30-50/month cheaper than G in most markets. The second most popular plan right now.

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**Coverage Comparison Table — 2026 Medigap Standardized Plans**

| Benefit | A | B | C* | D | F* | G | K | L | M | N | |---|---|---|---|---|---|---|---|---|---|---| | Part A coinsurance & hospital costs (365 days) | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | Yes | | Part B coinsurance/copay | Yes | Yes | Yes | Yes | Yes | Yes | 50% | 75% | Yes | Yes** | | Blood (first 3 pints) | Yes | Yes | Yes | Yes | Yes | Yes | 50% | 75% | Yes | Yes | | Part A hospice coinsurance | Yes | Yes | Yes | Yes | Yes | Yes | 50% | 75% | Yes | Yes | | Skilled nursing coinsurance | No | No | Yes | Yes | Yes | Yes | 50% | 75% | Yes | Yes | | Part A deductible ($1,736) | No | Yes | Yes | Yes | Yes | Yes | 50% | 75% | 50% | Yes | | Part B deductible ($283) | No | No | Yes | No | Yes | No | No | No | No | No | | Part B excess charges | No | No | No | No | Yes | Yes | No | No | No | No | | Foreign travel emergency | No | No | 80% | 80% | 80% | 80% | No | No | 80% | 80% |

*Plan C and Plan F only available to those eligible for Medicare before Jan 1, 2020. **Plan N has up to $20 office visit copay and up to $50 ER copay.

The big story in that table: Plan G covers everything except the Part B deductible. Plan N covers everything Plan G covers except Part B excess charges, and adds those copays. Everything else — Plans A, B, K, L, M — represents varying degrees of incomplete protection that most people in good conscience shouldn't be recommending to someone headed into retirement with unpredictable health needs.

Plan G is the most popular Medigap plan in America right now, and honestly it's not close. When Plan F got closed to new enrollees in 2020, most agents and most beneficiaries landed on G as the obvious replacement — and they were right.

Here's what Plan G actually does for you:

You pay your Part B deductible once a year — $283 in 2026. That's it. One payment, one time, and then Plan G covers 100% of everything else Original Medicare approves. Every Part B coinsurance charge (that 20% Medicare normally leaves on you), gone. Every Part A hospital deductible ($1,736), gone. Every skilled nursing facility coinsurance charge, gone. If you have emergency medical care abroad, 80% covered. If a doctor bills Medicare excess charges (up to 15% above Medicare's approved amount), covered.

The practical experience of having Plan G is this: you go to the doctor, you get care, Medicare processes the claim, and your Medigap policy pays whatever's left. You almost never get a bill. The $283 annual deductible might hit in January when you have your first appointment of the year. After that, you're coasting.

For someone who's 65 and healthy, the premium usually runs $130–$180/month nationally — though this swings a lot by state. Florida and New York tend to run higher. Parts of the Midwest run lower. At $150/month, you're paying $1,800/year in premiums plus $283 deductible = $2,083 total annual out-of-pocket exposure in the absolute worst case. For most people, that worst case never happens — the deductible is your only actual expense most years.

For comparison, without Medigap, a single hospital stay can cost you $1,736 in Part A deductible alone. A cancer diagnosis, a heart attack, a hip replacement — any of those could rack up tens of thousands of dollars in 20% coinsurance. Plan G turns that unlimited exposure into a known, capped number.

Who Plan G is right for:

People who want predictability. You know your maximum annual out-of-pocket is basically $283 + premiums. Done. People who go to the doctor regularly and don't want to track copays every visit. People who travel (especially internationally, given the foreign travel benefit). And honestly, people who just don't want to think about healthcare bills during retirement. That mental quiet is real value that doesn't show up in a spreadsheet.

Who might want to look elsewhere:

If you're in exceptional health, barely use the healthcare system, and want the lowest possible premium, the High Deductible Plan G might be worth a look (covered later). If you're somewhere in the middle — moderate health, occasional doctor visits — Plan N deserves a serious look before you default to G.

One thing worth knowing: Plan G premiums from the same insurer can vary dramatically by age (we'll get into rating types soon). Shopping around at 65 is critical. Two companies selling identical Plan G coverage can differ by $50-80/month in the same zip code. That's $600-$960/year for the exact same policy.

Plan N is the number two most popular Medigap plan, and for a certain type of enrollee it's genuinely the smarter buy. Let's actually understand what you're trading.

Plan N covers everything Plan G covers with two exceptions:

First, it doesn't cover Part B excess charges. That's what happens when a doctor doesn't accept Medicare assignment — they can charge up to 15% above Medicare's approved amount. In practice, this is less common than it used to be. Most doctors accept assignment. But some don't — certain specialists in certain markets. If you travel a lot or live somewhere with high concentrations of non-participating physicians, this matters. If you're in a rural area or your regular doctors all accept Medicare assignment (you can verify this at Medicare.gov), the excess charge risk is small.

Second, Plan N has copays. Up to $20 for some office visits. Up to $50 for emergency room visits — but here's the part worth knowing: if you actually get admitted to the hospital from the ER, that $50 ER copay is waived. So you're only paying $50 when you go to the ER, use the ER, and go home without being admitted. That's a very specific scenario.

In exchange for accepting those two limitations, you typically pay $30-50/month less in premiums than Plan G. In some markets the spread is even wider.

Nationally, Plan N premiums at age 65 run roughly $90-140/month. Plan G runs $130-180/month. The overlap in those ranges is real — in some markets they're close. In others there's a $60+/month gap. You have to shop your specific zip code.

Who Plan N is right for:

People who are reasonably healthy and expect to see the doctor a handful of times per year — not chronically or intensively. People who can confirm their regular doctors accept Medicare assignment. People who want the predictability of a Medigap policy (no network restrictions, no prior authorizations) but also want the lower premium that comes from accepting some small cost-sharing. Younger enrollees at 65 who are healthy and want to minimize costs while still having comprehensive protection.

The honest reality: for a lot of 65-year-olds in good health, Plan N is the better financial choice. The math only swings toward G if you're visiting the doctor frequently enough that $20 copays add up beyond the premium savings. We'll run that math explicitly in the next section.

This is the section most guides gloss over. Let's actually do the numbers.

Assumptions: You're 65, buying in a market where Plan G runs $155/month and Plan N runs $115/month. That's a $40/month ($480/year) premium difference in G's favor for N. Both plans make you pay the $283 Part B annual deductible regardless.

Now let's run three actual scenarios.

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**Scenario 1: Healthy Year — 3 Doctor Visits, No ER**

Plan N wins by $420. If you have a healthy year and barely use the system, N saves you real money.

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**Scenario 2: Moderate Year — 12 Doctor Visits, 1 ER Visit (not admitted)**

Plan N still wins, by $190. Even at 12 doctor visits, Plan N's premium savings haven't been completely eroded by copays.

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**Scenario 3: Heavy Use Year — 20 Doctor Visits, 2 ER Visits, 1 Non-Participating Specialist Charging Excess**

Plan G wins by $170. And this is a really heavy year — 20 office visits is a lot.

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What this tells you: the break-even point is somewhere around 15-18 doctor visits per year, depending on your specific premium spread. If you're under that threshold, N is usually the better buy. If you're managing a chronic condition that has you at the doctor constantly — 20+ visits, regular specialist care — G starts to make more sense.

But here's the thing people miss: this is year one math. Plan G and Plan N premiums both increase over time. The gap between them tends to stay roughly proportional, so the relative math doesn't change dramatically. What does change is your health — so the person buying Plan N at 65 who's healthy might reasonably say "I'll switch to G if my health situation changes." Whether you can actually make that switch without underwriting is a separate question (covered in the switching section) — but the strategy is legitimate.

One more thing: if you're in California, Oregon, or a birthday rule state, you have an annual window to switch plans without underwriting. That changes the calculus — Plan N becomes even more attractive if you know you have an annual off-ramp to upgrade to G if you need it.

This is probably the most important section in the entire guide for long-term financial planning, and it's consistently the thing brokers don't explain clearly.

There are three ways insurance companies can set Medigap premiums. The method they use will determine how fast your premium grows over time — and the difference can be thousands of dollars by the time you're 80.

**Attained-Age Rating**

Your premium is based on your current age — the age you've "attained." So when you turn 66, your premium goes up because you're now 66. When you turn 70, it goes up again. Every year, as you age, your rate increases. And that increase is on top of any general inflation-based increases the company might apply industry-wide.

Attained-age is the most common rating method. Most major carriers use it. Premiums start lowest (which is why it looks attractive at 65), but they climb the fastest over time. By your mid-70s and into your 80s, premiums that looked reasonable at 65 can feel brutal.

Typical attained-age trajectory for Plan G: starts at $155/month at 65, might be $200+ at 72, $260+ at 78, $320+ at 82. These aren't exact numbers — they vary by carrier and location — but the direction is predictable.

**Issue-Age Rating**

Your premium is locked to the age you were when you first bought the policy. If you enrolled at 65 and your rate was $180/month, that rate doesn't go up just because you turned 70. It can still go up for other reasons — healthcare cost inflation, claims experience in your area — but age alone doesn't drive increases.

Issue-age policies typically start higher than attained-age policies at 65 (since the insurer knows they can't raise your rate as aggressively later). But over a 10-15 year period, issue-age policies often end up cheaper in total. The math depends on how long you stay on the policy and what inflation rate applies.

Fewer carriers offer true issue-age policies, and availability varies by state.

**Community-Rated (No-Age Rating)**

Everyone in the pool pays the same rate regardless of age. A 65-year-old and a 78-year-old with the same Plan G from the same company pay the same premium. Rates can go up over time due to claims experience and inflation, but age is irrelevant.

Community-rated plans are available in a handful of states (Massachusetts, Minnesota, and Wisconsin have standardized their own Medigap rules). They often have higher starting premiums but the most stable long-term trajectory.

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So which rating type should you look for?

Honestly, if you're in a state where issue-age or community-rated policies are available, they're worth running the 10-year comparison. For most people in most states, attained-age is what you'll encounter — the key is knowing that the premium you're quoted at 65 is not the premium you'll be paying at 75. Budget accordingly.

When comparing carriers, always ask the agent or broker to show you the 5-year and 10-year rate history for that specific plan and company. Some carriers are notoriously aggressive with rate increases. Others are stable. That track record matters as much as the starting premium.

A carrier with a $145/month Plan G premium and a history of 8-10% annual increases will cost you more by year five than a carrier starting at $165/month with 3-4% annual increases. Do the math on year five, not year one.

This is the window everyone warns you not to miss, and they're right to.

When you first enroll in Medicare Part B, you get a 6-month Medigap Open Enrollment Period (OEP). It starts the first month you're both age 65 or older AND enrolled in Part B. It cannot be extended and it cannot be repeated — at least not under federal law (state rules may differ).

During this 6-month window, insurance companies must sell you any Medigap policy they offer in your state. They cannot deny you coverage, they cannot charge you more because of health conditions, and they cannot impose waiting periods for pre-existing conditions. This is called guaranteed issue — and it is an enormous benefit that disappears the moment the window closes.

This is real. Common conditions that cause underwriting problems: diabetes, heart conditions, COPD, cancer history, recent surgeries, obesity at certain thresholds, sleep apnea, kidney disease. It's not a short list.

So here's the practical advice: if you're turning 65 and enrolling in Part B, buy the Medigap policy you want during the open enrollment window. Don't wait to see how you feel. Don't delay because you feel healthy right now. Your health at 65 may be excellent — great! That makes you a perfect candidate for the best policy at the best price. But if you wait two years and then develop something, you may find yourself locked out of Medigap or paying rated premiums forever.

A few timing notes:

You can actually apply for Medigap up to 6 months before your Part B effective date in some states — check with your state's rules, but getting ahead of the window is smart.

If you're still working past 65 and enrolled in employer coverage, your 6-month window starts when you enroll in Part B — not when you turn 65. So delaying Part B enrollment (because you have qualifying employer coverage) also delays your Medigap OEP, which can actually work in your favor.

And critically: the 6-month clock doesn't restart. If you enrolled in Part B at 65, the window opened and closed six months later. There's no do-over. Outside that window, you need a guaranteed issue right or you're subject to underwriting. Full stop.

Lost your Medigap OEP? Or never got around to enrolling and now you have a health issue? There are specific circumstances — defined in federal law — where you have a guaranteed issue right to buy Medigap without underwriting even outside your open enrollment window.

These situations basically represent moments when the system recognizes you're losing coverage through no fault of your own.

The main federal guaranteed issue triggers:

**Medicare Advantage trial period** — You're in Medicare Advantage and it's your first year. You try it, decide you hate it, and want to switch back to Original Medicare + Medigap. Federal law gives you a guaranteed issue right within the first 12 months to buy Medigap Plans A, B, C, D, F (if eligible), G, K, or L without underwriting. This is sometimes called the "trial right." It's a legitimate strategy: try Advantage, if it doesn't work for you, exercise this right.

**Medicare Advantage plan leaving the area or terminating** — Your MA plan is discontinued or you move out of the plan's service area. You get a guaranteed issue right to buy certain Medigap plans.

**Losing other coverage** — You're covered under an employer group health plan that ends. You retire. Your union coverage ends. You lose Medicaid. In these situations, you typically get a 63-day guaranteed issue window from when coverage ends.

**Medigap insurer goes bankrupt or leaves the market** — If your current Medigap carrier exits your state or becomes insolvent, you can switch without underwriting.

**Moving out of a Medigap SELECT plan's service area** — If you had a SELECT plan (a type of Medigap with network restrictions) and you move somewhere that plan doesn't serve, you get guaranteed issue to buy a comparable plan.

Important: guaranteed issue rights apply to specific plans, not all plans. Federal law specifies which plans you can buy under each type of GI event. It's not a blank check — but it usually covers the core plans (A, B, C, D, F if eligible, G, K, L).

State protections: Several states extend guaranteed issue beyond federal minimums. California, Connecticut, Maine, Massachusetts, Missouri, New York, and others have state-specific GI rights that are more generous than federal law. In New York, for example, insurers must offer Medigap on a guaranteed issue basis year-round — no OEP required. That's an extraordinary consumer protection.

Bottom line: if you missed your open enrollment window, don't assume you're out of options. Know what triggered your need for coverage and check whether a GI right applies. A good independent insurance broker can map this for your specific situation.

Remember: Plan G from Company A and Plan G from Company B have identical benefits. You're shopping on premium, rate stability, financial strength, and customer service. Here's an honest look at the major players.

**AARP/UnitedHealthcare**

The biggest name in Medigap. UHC underwrites AARP-branded policies and they're sold under the AARP umbrella — meaning you get access to AARP member services as part of the package. Nationwide availability, strong financial ratings, and historically one of the lowest complaint rates in the industry.

The AARP brand also means they market heavily, which cuts both ways. They're easy to find and easy to buy from. But their premiums aren't always the most competitive, especially in markets with strong regional carriers. Check their 5-year rate history before committing — in some markets they've had notable increases.

A.M. Best rating: A (Excellent). JD Power satisfaction scores: consistently above average.

**Mutual of Omaha**

The gold standard for rate stability. Mutual of Omaha is consistently cited by independent agents as one of the most predictable pricing carriers — meaning fewer surprise rate spikes. Their Plan G premiums are competitive, and they offer household discounts of up to 12% if you and a spouse (or another adult in your household) are both enrolled.

A.M. Best rating: A+ (Superior). Excellent financial strength. Very low complaint index. If you want a carrier with a 60+ year track record in Medigap and a reputation for not jacking rates every year, Mutual of Omaha deserves serious consideration.

**Cigna**

Strong financial footing, national footprint, and competitive rates particularly for Plan G and Plan N in certain markets. Cigna tends to do well in the under-70 age bands. Their wellness extras — 24/7 nurse line, health tools — are nice but secondary to the actual pricing math.

A.M. Best: A (Excellent). Decent complaint history. Worth getting a quote for comparison.

**Blue Cross Blue Shield (Various affiliates)**

BCBS isn't a single company — it's a federation of regional carriers. In some markets (like Blue Cross Blue Shield of Michigan or Highmark in Pennsylvania), they're legitimately the best option. In other markets their Medigap rates aren't competitive. You need to check your specific state affiliate. Brand loyalty to BCBS from your working years doesn't automatically mean they're your best Medigap choice.

**Aetna (CVS Health)**

Competitive in many markets, especially Plan G. Since CVS acquired Aetna, they've pushed some wellness and pharmacy integrations. Financially solid. A.M. Best: A. Premiums vary significantly by region — strong in some areas, less competitive in others.

**Transamerica**

Often competitive in the 65-68 age band. Not always the best at older ages. Worth a quote, especially if you're on the younger end of enrollment.

**State Farm**

Where available, State Farm Medigap is often quite competitive and they trade on strong agent relationships. Limited to certain states.

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The honest advice here: don't pick a carrier from an article. Use an independent broker who has access to all or most carriers in your state, ask them to pull quotes from at least 5-6 companies, and ask specifically about rate increase history over the past 5 years for each carrier. The starting premium is only half the story. The trajectory is the other half.

Brand recognition means almost nothing in Medigap. The benefits are identical. Pay attention to price and rate stability.

Every Medigap policy you buy will go up in price over time. Not maybe — will. The question is how fast, which determines whether your plan is still worth keeping at 75 or 82.

There are three main drivers of Medigap rate increases:

**1. Age-based increases (attained-age policies)** As covered in the rating types section, attained-age policies raise your premium as you age. This is a contractual, predictable increase built into the product. Some carriers are more aggressive here than others. Ask to see how much the rate changes at specific age milestones — 67, 70, 75, 80.

**2. General rate increases** All carriers file rate increases with state insurance regulators annually based on claims experience, healthcare cost trends, and overall portfolio performance. These can hit even issue-age and community-rated policies. A "stable" carrier might still apply 3-5% annual general increases. A poorly managed carrier might apply 10-15%. State regulators must approve these increases, but approval isn't automatic denial.

**3. Closed block premium spiral** This is the sneaky one. When a carrier stops marketing aggressively (or changes its strategy), their existing Medigap policyholders get older while no new younger enrollees come in. The pool gets sicker. Claims go up. The carrier raises rates to cover claims. Healthier members leave. The pool gets even sicker. Rates spiral. If you're with a carrier that's winding down its Medigap business, this can be a brutal trajectory.

How do you predict rate increases?

When should you actually switch?

If your premium has increased to the point where another carrier can offer you the same plan for meaningfully less — AND you can pass underwriting — it may make sense to switch. The math needs to work: the savings over the remaining years you expect to hold the policy needs to exceed any underwriting risk (since applying may expose you to denial).

Birthday rule states (covered in the next section) change this calculus entirely — in those states, you have an annual window to shop without underwriting, which makes switching less scary and more routine.

This is genuinely one of the best consumer protections in the Medigap world, and most people have no idea it exists.

Several states have enacted what's commonly called the "birthday rule" — a law that gives Medigap policyholders a window around their birthday every year to switch to an equal or lesser plan without medical underwriting. No health questions. No denial risk. Just switch.

Here's where the birthday rule currently applies and how each state does it:

**California** The OG birthday rule state. You have a 60-day window: starting 30 days before your birthday and ending 60 days after. You can switch to any plan with equal or lesser benefits from ANY carrier in California — not just your current one. That's a meaningful freedom. California also specifically allows switching from Plan F to Plan G (which has lesser benefits by $283/year in deductible terms) as a qualifying move.

**Oregon** Similar to California. 30 days before birthday to 30 days after — a 60-day window. Can switch to any carrier with equal or lesser benefits. No health questions.

**Missouri** Slightly different mechanism. Missouri's rule is anniversary-based rather than birthday-based — you can terminate your current policy and buy the same plan from a different company within 30 days of your policy anniversary. Up to 63 days from termination to get the new plan. Essentially a same-plan carrier switch once per year without underwriting.

**Illinois** Enrollees ages 65-75 get a 45-day window starting on their birthday to switch to an equal or lesser plan from their CURRENT carrier. Note: Illinois limits this to the same carrier (unlike California and Oregon), and only applies up to age 75.

**Delaware** As of January 1, 2026, Delaware joined the birthday rule group. 30 days before to 30 days after birthday, equal or lesser plan, any carrier.

**Nevada** Has additional Medigap protections including a birthday rule provision. Check current Nevada regulations for the precise window details.

**Idaho** Birthday rule — 63-day window around birthday for equal or lesser plan.

**Louisiana** Annual birthday rule, 30-day window.

**Other states are actively considering birthday rule legislation** — the trend is clearly in this direction. Check your state insurance commissioner's website for current status.

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Why does this matter for your planning?

If you live in a birthday rule state, the calculus for choosing Plan G vs Plan N changes somewhat. You could start on Plan N (lower premiums while you're healthy), and if your health deteriorates or you find you're using the system a lot, use your annual birthday rule window to switch to Plan G — without underwriting, without getting denied. That's a real strategy, not just theory.

It also means you should be shopping annually in these states. If another carrier is offering the same plan for less and your rates have climbed, your birthday window is your free pass to move. Use it.

This is the comparison that makes insurance agents nervous and that sales pitches on both sides manipulate. Let's be straight about it.

Medicare Advantage (Part C) and Medigap are fundamentally different approaches to solving the same problem — the gaps in Original Medicare. They're not the same product, and "which one is better" genuinely depends on your situation. But there are things that are objectively true about each.

**The structure difference**

Medigap keeps you in Original Medicare. Your claims go through Medicare. Any doctor or hospital that accepts Medicare, accepts you. No networks to worry about. No prior authorizations for most things. No referrals needed to see a specialist. The insurance company writes checks based on what Medicare approves.

Medicare Advantage replaces Original Medicare with a private insurance plan. The plan's network, rules, and cost structure govern your care — not Medicare's. Most MA plans have HMO or PPO networks. You may need referrals. You may need prior authorizations for imaging, procedures, or specialist visits. The plan's out-of-pocket maximum governs your worst-case cost exposure (up to $9,250 in 2026 for in-network services).

**The cost difference**

For 2026, around 60% of Medicare Advantage plans have a $0 monthly premium. That looks like a massive win on paper. Add in dental, vision, hearing, and gym membership benefits that Medigap doesn't offer, and MA looks like an obvious choice.

But zero premium isn't zero cost. MA has copays, coinsurance, and deductibles every time you use services. With a $9,250 annual out-of-pocket maximum, a serious health event could cost you nearly $10,000 in a single year.

Medigap Plan G runs $130-180/month = $1,560-$2,160/year in premiums, plus $283 deductible. A hospital stay, a cancer diagnosis, a heart attack — your additional cost is essentially $0 beyond that.

Studies consistently show that Medicare Advantage beneficiaries with significant health needs spend more out-of-pocket than comparable Medigap beneficiaries. The zero premium is a front-loaded discount. The back-end cost exposure is real.

**The 5-year cost comparison**

MA looks cheaper over 5 healthy years.

Medigap looks dramatically cheaper when you actually get sick.

The fundamental trade-off is this: Medicare Advantage is a bet that you'll stay healthy. Medigap is insurance against not staying healthy. At 65, you don't know which category you'll fall into.

**Other considerations:**

Network restrictions with MA are real. Snowbirds, frequent travelers, or people who live in multiple states often find MA plans don't work well — the network that covers you in Florida may not cover you in Arizona. Medigap works everywhere Medicare is accepted, including nationally and abroad.

Dental, vision, and hearing through MA sound good, but the benefits are often limited in ways the ads don't emphasize. $500 of dental coverage sounds helpful until you need a crown or an implant. These benefits have real value but shouldn't be the primary reason to choose MA over Medigap.

Going back to Medigap after a stint in Medicare Advantage is possible (via the trial right in year one, or via guaranteed issue rights), but after year one, switching to Medigap requires passing underwriting in most states. If your health has changed during your time in MA, you might be stuck.

Bottom line: if you're in good health, have a limited budget, and live in one place with a strong MA network, Medicare Advantage can be a reasonable choice. If you have significant health conditions, travel frequently, prioritize provider flexibility, or simply want to never think about healthcare bills in retirement, Medigap almost always wins the total-cost analysis over time.

Here's something most Medicare educational content buries or skips: if you're under 65 and on Medicare because of a disability or End Stage Renal Disease (ESRD), buying Medigap is hard. And in some states, basically impossible.

Federal law does not require insurance companies to sell Medigap policies to Medicare beneficiaries under age 65. That's the default rule. If you're 55 and on Medicare due to a disability, an insurer in most states can simply say no — legally.

But states can and do require more. As of 2026, approximately 35 states require insurers to offer at least one Medigap plan to under-65 Medicare beneficiaries. That's progress. But it means roughly 15-16 states still offer no required protection, and people on disability Medicare in those states face a genuine coverage gap.

States that require at least some under-65 Medigap coverage: Arkansas, California, Colorado, Connecticut, Delaware, Florida, Georgia, Hawaii, Idaho, Illinois, Indiana, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, New Hampshire, New Jersey, New York, North Carolina, Oklahoma, Oregon, Pennsylvania, South Dakota, Tennessee, Texas, Vermont, Virginia, and Wisconsin.

States where under-65 Medigap isn't required: Alabama, Alaska, Arizona, Iowa, Nebraska, Nevada, New Mexico, North Dakota, Ohio, Rhode Island, South Carolina, Utah, Washington, West Virginia, and Wyoming.

Even in states that require some coverage, there are catches. Insurers often aren't required to offer all plans — just one. And premiums for under-65 enrollees can be much higher. California limits plans for under-65 enrollees. States that do require coverage often don't cap how much insurers can charge — and premiums for a 52-year-old with a disability can be 2-3x what a 65-year-old pays.

ESRD complicates things further. Dialysis patients have specific Medigap rights that differ from standard disability Medicare, and several states specifically carve out ESRD from under-65 requirements.

If you're under 65 on Medicare, the moves are: check your state's rules, contact your State Health Insurance Assistance Program (SHIP) for free counseling, and get quotes immediately when you enroll in Part B since you do get an open enrollment window when you first enroll regardless of age.

This is one area where the system genuinely fails people, and the inconsistency by state is frustrating. Know your state's rules before you need them.

There's a lower-premium version of Plan G that most people aren't aware of, and for the right person it's a genuinely interesting option.

High Deductible Plan G (HDG) works like this: it has all the same ultimate coverage as regular Plan G, but you pay the first $2,950 in Medicare-approved costs out of pocket before the plan kicks in. Once you hit that deductible, the plan covers everything just like regular Plan G.

In exchange for accepting that $2,950 annual risk, you pay dramatically lower premiums. In many markets, HDG premiums run $40-70/month at age 65. Compare that to $130-180/month for regular Plan G. You're saving $60-140/month — $720-1,680/year — in premiums.

The break-even math: if you have a year with significant healthcare costs and hit the full $2,950 deductible, your total cost is $2,950 + premiums paid. With regular Plan G, your total is $283 (Part B deductible) + premiums. For HDG to make sense, the premium savings need to exceed the deductible risk over time.

Here's how it plays out: if regular Plan G costs you $1,800/year in premiums and HDG costs $720/year, you're saving $1,080 annually. In a healthy year where you spend next to nothing, you're $1,080 ahead. In a terrible year where you hit the full $2,950 deductible, you're paying $2,950 + $720 = $3,670, compared to $1,800 + $283 = $2,083 for regular G — so you're $1,587 behind. It takes roughly 1.5 healthy years to make up one bad year.

Who should consider HDG?

People who are genuinely healthy, don't have chronic conditions, have adequate savings to cover a $2,950 deductible without financial stress, and are comfortable taking a calculated risk in exchange for premium savings. This works well for someone who's 65, active, healthy, not on regular prescription maintenance care (though Part D handles drugs separately), and wants to keep their monthly costs low.

High Deductible Plan F works the same way but is only available if you were eligible for Medicare before January 1, 2020. Same deductible structure, slightly different underlying coverage (covers the Part B deductible once you clear the overall HDG/F deductible).

One practical note: keeping track of what applies toward your $2,950 annual deductible requires some diligence. You need Explanation of Benefit statements from Medicare to know where you stand. Not everyone wants that administrative overhead, even if the math works.

At some point, you might want to switch Medigap plans or carriers. Maybe your premium has gotten too high. Maybe you want to change from Plan N to Plan G because your health situation changed. Maybe you moved to a different state. Here's what you actually need to know.

**The default situation: underwriting applies**

Outside of protected windows, switching Medigap plans means applying for a new policy. The insurer can review your health history, ask medical questions, and decide whether to approve you, decline you, or approve you with a pre-existing condition waiting period. Common denial reasons include recent heart attack or stroke, cancer (active or in recent years), kidney disease, certain autoimmune conditions, diabetes with complications, and more.

This is the risk of switching — if your health has changed since your original open enrollment, you may not be able to get coverage. This is why buying the right plan during OEP is so important.

**When you can switch without underwriting:**

1. **Birthday rule states** — If you're in California, Oregon, Delaware, Idaho, Louisiana, or other birthday rule states, you have an annual window. Use it every year to shop. If your current rate is climbing, your birthday is your free pass to move.

2. **Trial right (Medicare Advantage trial period)** — If you were on Medigap, switched to MA, didn't like it, and want to come back within 12 months, you can return to your previous Medigap policy or buy a similar one without underwriting. This is a federal right.

3. **Loss of coverage GI right** — The various guaranteed issue situations described earlier apply here too. Losing employer coverage, MA plan terminating, etc.

4. **New York and Connecticut** — These states have year-round guaranteed issue for Medigap. You can switch anytime without underwriting. An extraordinary consumer protection.

5. **Moving to a different state** — If you move and your current Medigap carrier doesn't offer coverage in your new state, you may have protections to enroll in a new plan.

**Same-carrier, same-plan switches** (downgrading to a less comprehensive plan):

Many carriers will allow you to downgrade to a less comprehensive plan within their product offerings without full underwriting. Switching from Plan G to Plan N with the same insurer is sometimes processed as a plan change rather than a new application. Not all carriers do this, and the rules vary — but it's worth asking if you want to reduce premiums without going through full underwriting.

**The 30-day free look period:**

Most states require a 30-day free look period on new Medigap policies — you can cancel within 30 days for a full refund if you change your mind. Don't cancel your existing policy until you're sure the new one is in force and you've passed the free look period.

**Bottom line on switching:** it's harder than it looks for most people, which is another argument for getting this right the first time during OEP. But it's not impossible, especially in birthday rule states and states with strong consumer protections.