Complete Guide to Medigap Plans – All 10 Letters Explained (2026)

Medigap plans guide — if you are turning 65 or already on Original Medicare, this is the resource you need. Medicare Part A and Part B leave significant coverage gaps. Hospital stays, doctor visits, and skilled nursing care all come with deductibles, coinsurance, and copays that add up fast. In 2026, the Part A deductible alone is $1,736 per benefit period. The Part B deductible is $283 per year.

After that, you still owe 20% of most outpatient services with no annual out-of-pocket maximum. That 20% has no cap — meaning a $500,000 cancer treatment could leave you owing $100,000. Medigap policies, also called Medicare Supplement Insurance, fill these gaps. There are 10 standardized plan letters available in most states. Each letter offers a different level of coverage at a different price point. This medigap plans guide walks you through every option so you can make a confident, informed decision about your healthcare coverage in 2026 and beyond.

What Is a Medigap Plans Guide and Why Does It Matter?

A medigap plans guide is a comprehensive resource that explains how Medicare Supplement Insurance works. Medigap policies are sold by private insurance companies. They help pay for out-of-pocket costs that Original Medicare does not cover. These costs include deductibles, copays, and coinsurance under Part A and Part B.

Understanding your options matters because the financial stakes are high. Original Medicare has no annual out-of-pocket maximum. A serious illness or injury can result in tens of thousands of dollars in medical bills. Medigap fills those gaps — but only if you choose the right plan during the right enrollment window. According to CMS data, approximately 13.7 million Americans are enrolled in Medigap policies. That number continues to grow each year as more baby boomers turn 65.

This medigap plans guide is essential for three groups of people. First, anyone approaching age 65 who wants to understand their Medicare options. Second, current Medicare beneficiaries considering switching from Medicare Advantage to Original Medicare with a supplement. Third, family members helping aging parents navigate their healthcare coverage decisions.

The federal government standardizes Medigap plans into 10 letter designations. This means Plan G from UnitedHealthcare covers the exact same benefits as Plan G from Mutual of Omaha. The only differences between carriers are price, customer service, and financial stability. This standardization makes a thorough medigap plans guide especially valuable — once you understand the letters, you can shop confidently.

Medigap Plans Guide: The 10 Standardized Plan Letters

The foundation of any medigap plans guide is understanding the 10 plan letters. Congress standardized these plans in 1990 through the Omnibus Budget Reconciliation Act. Each letter covers a specific combination of benefits. Plans cannot add or remove benefits — what the letter covers is set by federal law.

Here is what each plan covers in 2026. The table below shows the complete benefit breakdown for all 10 Medigap plan letters referenced in this medigap plans guide.

*Plan N charges copays of up to $20 for office visits and up to $50 for ER visits that do not result in admission.

Plans C and F deserve special attention in this medigap plans guide. The MACRA legislation of 2015 banned the sale of Plans C and F to anyone newly eligible for Medicare on or after January 1, 2020. If you turned 65 before that date, you can still buy and keep these plans. Everyone else should focus on Plan G or Plan N as their primary options.

How This Medigap Plans Guide Works: Enrollment Step by Step

Timing is everything in this medigap plans guide. Your Medigap Open Enrollment Period (OEP) is the most important window in your Medicare journey. It lasts exactly 6 months. It starts on the first day of the month you turn 65 and are enrolled in Medicare Part B. During this period, insurance companies must sell you any Medigap policy they offer — regardless of your health.

Outside your OEP, insurers in most states can use medical underwriting. They can deny you coverage or charge higher premiums based on pre-existing conditions. This is why every medigap plans guide emphasizes acting during your OEP. Missing this window can cost you thousands of dollars or lock you out entirely.

There are also guaranteed issue rights outside the OEP. These apply in specific situations. If your Medicare Advantage plan leaves your area, you have a guaranteed right to buy a Medigap policy. If your employer group coverage ends, you also qualify. These protections are limited to Plans A, B, C, F, K, and L in most cases. Check your state’s specific rules for additional protections.

Comparing Your Options: A Medigap Plans Guide to the Top Choices

For most people reading this medigap plans guide in 2026, the real decision comes down to three plans. Plan G is the most popular Medigap plan in America. It covers everything except the annual Part B deductible of $283. According to industry data, Plan G now holds approximately 39% of the entire Medigap market — over 5 million enrollees.

Plan N is the second most popular choice. It costs less than Plan G but requires small copays. You pay up to $20 for doctor office visits and up to $50 for emergency room visits that do not result in hospital admission. Plan N also does not cover Part B excess charges. However, over 99% of doctors accept Medicare assignment, making excess charges rare. Plan N holds roughly 10% of the Medigap market with over 1.6 million enrollees.

Plan F remains popular among those who were eligible for Medicare before January 1, 2020. It covers everything — including the Part B deductible. Plan F still accounts for about 36% of all Medigap enrollees. However, its pool is aging and closed to new members, which means premiums will likely increase faster over time. This is a critical insight in any medigap plans guide — a shrinking risk pool generally leads to higher rates.

For beneficiaries on a tighter budget, this medigap plans guide also highlights Plan K and Plan L. These cost-sharing plans cover 50% and 75% of most benefits, respectively. They include annual out-of-pocket limits — $8,000 for Plan K and $4,000 for Plan L in 2026. Once you hit that limit, the plan pays 100% for the rest of the year.

Costs Associated with Your Medigap Plans Guide Decision

Premiums are the biggest cost factor in your medigap plans guide evaluation. Medigap premiums vary widely based on three pricing methods. Understanding these methods can save you thousands of dollars over the life of your policy.

Community-rated (no-age-rated): Every policyholder pays the same premium regardless of age. A 65-year-old and an 85-year-old pay the same base rate. These policies cost more at age 65 but increase more slowly over time. Issue-age-rated: Your premium is based on your age when you buy the policy. It does not increase due to aging — only inflation and medical cost adjustments. Attained-age-rated: Your premium increases as you get older. These policies are cheapest at 65 but become the most expensive option over time. Most carriers use attained-age pricing.

Beyond premiums, your medigap plans guide cost analysis should include what you pay out of pocket. With Plan G, your only annual cost beyond premiums is the $283 Part B deductible. With Plan N, you also face copays and potential excess charges. With Plan K, you could pay up to $8,000 before the plan covers everything. The math often favors Plan G or Plan N for total cost predictability.

Premium increases are a reality for every Medigap policy. According to CMS filings, carriers requested Plan G increases ranging from 6% to over 15% in recent years. Switching carriers can reset your premium — but only if you can pass medical underwriting. Some states like New York, Connecticut, and Massachusetts offer annual open enrollment windows or continuous guaranteed issue protections that make switching easier. Always check your state’s Medigap rules before assuming you can switch freely.

Top Companies in Your Medigap Plans Guide

Because Medigap benefits are standardized by federal law, choosing a carrier comes down to four factors. Price is first — premiums for the same plan letter can vary by 30% or more between carriers in the same ZIP code. Financial strength ratings matter because you want a company that will be solvent for decades. Customer service reputation affects your claims experience. And rate increase history tells you how aggressively a carrier raises premiums over time.

This medigap plans guide highlights the major national carriers. UnitedHealthcare (AARP) is the largest Medigap carrier by enrollment. They administer the AARP-branded Medicare Supplement plans and are available in most states. Mutual of Omaha is widely regarded for competitive pricing and predictable rate increases. They consistently rank among the top three Medigap carriers nationwide. Blue Cross Blue Shield affiliates operate independently by state and often hold dominant market positions in their regions.

Aetna (part of CVS Health) offers competitive Plan G and Plan N rates with household discounts for married couples. Cigna provides nationwide availability with additional perks like a 24/7 nurse helpline. Humana offers Medigap plans in select states with bundled dental, vision, and hearing discounts. Each of these carriers sells the same standardized benefits — so this medigap plans guide recommends comparing quotes from at least three to five carriers before enrolling.

A high-deductible option exists for Plans F and G. The 2026 high-deductible amount is $2,950. You pay all Medicare costs out of pocket until you reach that deductible. Then the plan covers everything. High-deductible Plan G premiums can be 60-70% lower than standard Plan G. This option suits healthy beneficiaries who want catastrophic protection at a lower monthly cost.

State-by-State Differences in Your Medigap Plans Guide

Federal standardization creates a baseline, but states add their own rules. This section of the medigap plans guide covers the most important state-level variations. Three states — Massachusetts, Minnesota, and Wisconsin — do not use the standard letter system at all. They have their own unique plan structures that were grandfathered in before federal standardization took effect.

Several states offer additional protections beyond the federal minimum. New York requires community rating on all Medigap policies and provides a continuous open enrollment period. Connecticut offers an annual 30-day birthday rule window to switch plans without underwriting. California, Missouri, Oregon, and Washington also have birthday rule provisions. These extra protections can make a significant difference in your medigap plans guide analysis. Check Medigap plans by state for the specific rules in your area.

Some states also mandate Medigap access for beneficiaries under 65 who qualify for Medicare due to disability. Federal law does not require this — only about 30 states have passed legislation guaranteeing under-65 access to Medigap. If you are under 65 and on Medicare, check your state insurance department website or visit our Medicare by state directory for details on availability and pricing in your state.

State insurance departments regulate premium increases. Carriers must file rate requests with the state Department of Insurance for approval. Some states are more aggressive at limiting increases. This medigap plans guide recommends checking your state DOI website for recent rate filings from your carrier. It provides valuable insight into future premium trends.

Medigap Plans Guide for Different Situations

Turning 65 and healthy: This medigap plans guide recommends Plan G as the default starting point. It offers near-complete coverage for a competitive premium. You only pay the $283 annual Part B deductible. If premiums are a concern, Plan N typically saves $30-$60 per month with minimal additional out-of-pocket exposure.

Turning 65 with chronic conditions: Predictability matters most when you use healthcare frequently. Plan G eliminates virtually all cost-sharing surprises. For beneficiaries with chronic conditions who see specialists regularly, the extra premium for Plan G over Plan N is usually worth the peace of mind. This is a key point in any medigap plans guide — those who use more care benefit most from comprehensive coverage.

Under 65 on Medicare due to disability: Your options depend entirely on your state. Not all states require carriers to sell Medigap to under-65 beneficiaries. Those that do often allow higher premiums. This medigap plans guide strongly recommends contacting your state SHIP (State Health Insurance Assistance Program) counselor for guidance specific to your situation. Medicare Advantage may be a more accessible alternative in states with limited under-65 Medigap access.

Budget-conscious retirees: Plan K and Plan L offer lower premiums in exchange for cost-sharing. Plan K covers 50% of most benefits with an $8,000 annual cap. Plan L covers 75% with a $4,000 cap. Plan M is another mid-range option that covers 50% of the Part A deductible. These plans work best for relatively healthy beneficiaries who want catastrophic protection without high monthly premiums.

Common Medigap Plans Guide Mistakes to Avoid

Mistake 1: Missing your Open Enrollment Period. This is the most expensive mistake in any medigap plans guide. Once your 6-month OEP expires, carriers can deny coverage or charge higher premiums based on your health. There are no annual Medigap open enrollment windows at the federal level. Procrastination can cost you coverage entirely.

Mistake 2: Choosing Plan F when Plan G is available. Plan F covers the Part B deductible. Plan G does not. The difference in coverage is exactly $283 per year. But Plan F premiums are often $300-$600 more per year than Plan G. Plus, Plan F’s risk pool is closed and aging. This medigap plans guide consistently recommends Plan G over Plan F for new enrollees who have a choice.

Mistake 3: Assuming Medigap covers prescription drugs. No Medigap plan sold after 2006 includes drug coverage. You need a separate Medicare Part D plan. Failing to enroll in Part D during your initial enrollment period triggers a late enrollment penalty of 1% per month for every month you went without creditable coverage.

Mistake 4: Not comparing carriers. Same plan letter, same benefits — but premiums can vary by hundreds of dollars per year. This medigap plans guide recommends getting quotes from at least three carriers. Use the Medicare Plan Finder on medicare.gov to see all available options in your ZIP code.

Mistake 5: Confusing Medigap with Medicare Advantage. You cannot have both. If you buy a Medigap policy, you must be on Original Medicare (Parts A and B). Medicare Advantage is an alternative to Original Medicare — not a supplement. This is one of the most common misconceptions addressed in any medigap plans guide.

Mistake 6: Ignoring the pricing method. An attained-age policy that costs $120 per month at 65 might cost $250 or more by age 80. A community-rated policy might cost $170 at 65 but stay closer to that level. This medigap plans guide urges you to ask about the pricing method before enrolling. Your state insurance department can tell you which methods are used by carriers in your area.

Mistake 7: Not understanding excess charges. If your doctor does not accept Medicare assignment, they can charge up to 15% above the Medicare-approved amount. Plans G and F cover these excess charges. Plans N, K, L, and most others do not. While over 99% of providers accept assignment, this medigap plans guide notes that the risk matters most for specialists and surgeons.

Mistake 8: Failing to review your plan annually. Medigap benefits do not change, but premiums do. Switching carriers for the same plan letter can save money — if you can pass underwriting. States with birthday rules make this easier. Reviewing your plan each year is a best practice in any medigap plans guide strategy.

How to Get Help with Your Medigap Plans Guide Decisions

SHIP Counselors: Every state has a State Health Insurance Assistance Program (SHIP). These counselors provide free, unbiased Medicare advice. They are trained by CMS and do not sell insurance. They can walk you through this medigap plans guide and help you compare plans. Call 1-800-MEDICARE (1-800-633-4227) to find your local SHIP office.

Medicare.gov: The official Medicare website has a Medigap policy search tool. Enter your ZIP code and it displays every available Medigap plan with carrier names and contact information. It also shows which plans each carrier offers. Use this alongside our medigap plans guide to research your options. You can also browse our complete library of Medicare guides for detailed breakdowns of every topic.

State Department of Insurance: Your state DOI regulates Medigap carriers and approves premium rates. Their website often publishes rate comparison guides showing premiums from every carrier in your state. This is one of the most valuable resources referenced in this medigap plans guide. Many state DOI offices also have consumer assistance hotlines.

Licensed insurance agents and brokers: Independent agents who represent multiple carriers can provide personalized quotes. They are paid by the insurance company — not by you. Make sure your agent is licensed in your state and represents at least three to five different Medigap carriers. A good agent complements this medigap plans guide with local market expertise and premium comparisons tailored to your age and ZIP code.

Frequently Asked Questions About Medigap Plans Guide Topics

What is the best Medigap plan in 2026?

Plan G is the most popular and widely recommended Medigap plan in 2026. It covers all gaps in Original Medicare except the $283 annual Part B deductible. It has the largest and most diverse risk pool of any currently available plan. For budget-conscious beneficiaries, Plan N offers strong coverage at a lower premium with small copays.

Can I buy Medigap if I have pre-existing conditions?

During your 6-month Open Enrollment Period, yes — carriers cannot deny you or charge more based on health status. Outside the OEP, most states allow medical underwriting. Some states like New York and Connecticut offer additional protections. This medigap plans guide recommends enrolling during your OEP whenever possible to guarantee access.

Does Medigap cover prescription drugs?

No. No Medigap plan sold after 2006 covers prescription drugs. You need a separate Medicare Part D prescription drug plan. Some older Medigap policies purchased before 2006 may include drug coverage, but these plans are no longer sold. Enroll in Part D during your Initial Enrollment Period to avoid late penalties.

Can I switch Medigap plans after I enroll?

You can apply to switch anytime, but outside your OEP you may face medical underwriting. Some states offer birthday rule provisions that allow switching without underwriting during a window around your birthday. Check your state’s specific rules in our state-by-state Medigap directory.

How much does Medigap cost per month?

Medigap premiums vary significantly by plan letter, carrier, age, location, and pricing method. According to CMS, premiums can range from under $100 per month for basic plans to over $300 per month for comprehensive plans in high-cost areas. This medigap plans guide recommends using medicare.gov or contacting local carriers for exact quotes based on your age and ZIP code.

What is the difference between Medigap and Medicare Advantage?

Medigap supplements Original Medicare by covering out-of-pocket costs like deductibles and coinsurance. Medicare Advantage replaces Original Medicare entirely with a private plan that often includes drug coverage and extra benefits. You cannot have both simultaneously. Medigap gives you provider freedom nationwide. Medicare Advantage typically uses provider networks. This medigap plans guide focuses on Medigap, but both paths have legitimate advantages depending on your healthcare needs and budget.

Final Thoughts on Your Medigap Plans Guide

This medigap plans guide has covered all 10 standardized plan letters, enrollment timelines, pricing methods, carrier options, and state-level variations. The most important takeaway is this — your Medigap Open Enrollment Period is your single best opportunity to secure comprehensive, affordable coverage. Do not let it pass without taking action.

For most new Medicare beneficiaries in 2026, Plan G offers the strongest combination of coverage and value. Plan N is an excellent alternative for those who want lower premiums and are comfortable with small copays. Compare quotes from multiple carriers — UnitedHealthcare, Mutual of Omaha, Aetna, BCBS, Cigna, and Humana all compete for your business, and premiums for the same plan letter can differ significantly.

Use this medigap plans guide as your starting reference, then take the next step. Visit Medigap plans by state to see what is available where you live. Contact your local SHIP counselor for free, personalized advice. And explore our complete Medicare guide library for detailed breakdowns of every plan letter — from Plan A through Plan N. The right Medigap policy can protect your retirement savings and give you peace of mind for decades. This medigap plans guide gives you the knowledge to choose wisely.

Compare Plan G vs Plan N

Which Medigap plan saves you more — Plan G with zero copays or Plan N with lower premiums? Enter your actual premium quotes and typical healthcare usage below. The calculator projects your total annual costs for each plan, shows your breakeven point, and gives you a clear recommendation. Everything runs in your browser — no data is collected.

Ready to explore your Medicare options? Use the official Medicare Plan Finder or contact your local SHIP counselor for free, unbiased help.

Official Sources & Resources

For verified Medicare information and enrollment help:

• Medicare.gov: medicare.gov
• CMS.gov: cms.gov
• NAIC Medigap Guide: naic.org
• KFF Medicare Research: kff.org/medicare
• Find Your SHIP: medicare.gov/contacts

Content last reviewed April 2026. If you notice any outdated information, please contact us.

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