Medicare Supplement Plans Explained (2026)

If you’ve been researching Medicare supplements, also known as Medigap, it’s common to feel confused by all the lettered plans like A, G, or N.  

They all sound official, but it’s not always clear how they’re different or how you’re supposed to choose.

In this guide, we’ll walk through all 10 Medicare Supplement plans, explain what each one does, and help you understand how they fit into Medicare coverage in 2026.

How Medicare Parts A and B Work

To help Medicare Supplement plans make sense, let's go over Original Medicare, which is made up of Part A and Part B.

Medicare Part A is hospital insurance. It helps pay for things like inpatient hospital stays, skilled nursing facility care after a hospital stay, hospice care, and some home health services. Most people don’t pay a monthly premium for Part A if they worked and paid Medicare taxes long enough.

Medicare Part B is medical insurance. It covers doctor visits, outpatient care, preventive services, durable medical equipment, and many medical tests and procedures. Part B has a monthly premium and typically pays 80% of approved medical costs, leaving you responsible for the remaining 20%.

This 20%, along with deductibles and coinsurance, is where many people feel caught off guard.

Why Medicare Supplements Matter

A Medicare Supplement helps cover gaps in coverage to keep money in your pocket. It works alongside Original Medicare (Parts A and B), letting you see any doctor who accepts Medicare and giving you more predictable medical costs throughout the year. These plans don’t include prescription drug coverage, so you must use them with a separate Medicare Part D plan.

A Quick Rule That Affects Your Options

Before we discuss the plans themselves, it is important to note if you became eligible for Medicare on or after January 1, 2020, you cannot enroll in Medicare Supplement Plan C or Plan F. These plans are still available, but only to people who were eligible for Medicare before that date.

Everyone else can choose from the remaining plans, which still offer excellent coverage options.

Medicare Supplement Plan A

Medicare Supplement Plan A (not to be confused with Medicare Part A) is the most basic Medicare Supplement plan, and every company that sells Medigap must offer it. It covers essential gaps like hospital coinsurance, doctor coinsurance, hospice care, and the first three pints of blood.

What it does not do is cover deductibles, skilled nursing facility costs, or foreign travel emergencies. Because of that, Plan A is usually chosen by people who want minimal coverage at the lowest possible premium.

Medicare Supplement Plan B

Medicare Supplement Plan B (not to be confused with Medicare Part B) includes everything Plan A covers but adds coverage for the Medicare Part A hospital deductible. That deductible can be significant during a hospital stay, so this extra protection can be appealing.

Other things, like skilled nursing care and foreign travel, are still not covered under this plan.

Medicare Supplement Plan C

Plan C (the supplement, not to be confused with Medicare Part C aka Medicare Advantage), offers strong, well‑rounded coverage, but only for people who were eligible for Medicare before January 1, 2020. It covers rehabilitation skilled nursing facility coinsurance, foreign travel emergency care, and both the Part A and Part B deductibles.

For those who qualify, Plan C minimizes out‑of‑pocket medical costs throughout the year.

Medicare Supplement Plan D

Plan D (the supplement, not to be confused with Medicare Part D, which covers prescription drugs), looks very similar to Plan C, but it does not cover the Part B deductible. Everything else is largely the same, including rehabilitation skilled nursing care and foreign travel emergencies.

Plan D is often chosen by people who want broad coverage but are comfortable paying the Part B deductible themselves.

Medicare Supplement Plan F

Plan F is the most comprehensive Medicare Supplement plan available. If Medicare approves a service, Plan F covers what Medicare does not, including deductibles, copays, coinsurance, and excess charges.

However, like Plan C, it is only available to people eligible for Medicare before January 1, 2020. Premiums are typically higher, but medical bills are extremely predictable.

Medicare Supplement Plan G

Plan G is the most popular Medicare Supplement plan in 2026, especially for people new to Medicare.

It works almost exactly like Plan F, with one difference: you pay the Part B deductible yourself. In 2026, that deductible is $283. After you pay it, Plan G covers nearly everything else Medicare approves, including excess charges and foreign travel emergency care.

Many people prefer Plan G because the premiums are usually lower than Plan F, and the annual deductible is relatively small.

Medicare Supplement Plan K

Plan K takes a different approach. Instead of covering most costs fully, it pays 50% of many Medicare expenses and includes an annual out‑of‑pocket maximum. Once you hit that limit, the plan covers 100% of approved costs for the rest of the year. In 2026, that maximum out-of-pocket expense is $8,000.  

Premiums for Plan K are lower, making it appeal to people who want protection against major medical events but don’t mind cost‑sharing.

Medicare Supplement Plan L

Plan L works similarly to Plan K but covers 75% of many costs instead of 50%. It also has a lower out‑of‑pocket limit than Plan K. That maximum out-of-pocket for 2026 is $4,000.

This plan tends to attract people who want some cost sharing without taking on too much financial risk.

Medicare Supplement Plan M

Medicare Supplement Plan M is designed to help keep monthly premiums lower by sharing some hospital costs. Instead of covering the Medicare Part A hospital deductible in full, Plan M pays 50% of the deductible, leaving you responsible for the other half, if you’re hospitalized.

Aside from that cost sharing, Plan M still covers many important gaps left by Original Medicare. It pays hospital coinsurance (including up to 365 extra hospital days), skilled nursing facility coinsurance, hospice care coinsurance, the first three pints of blood, and the 20% Part B coinsurance after the Part B deductible is met. It also includes limited foreign travel emergency coverage.

Plan M does not cover the Part B deductible or Part B excess charges. Because of this, it’s often chosen by people who are generally healthy, don’t expect frequent hospital stays, and want lower premiums while still having solid coverage.

Medicare Supplement Plan N

Medicare Supplement Plan N is often compared with Plan G because it offers similar protection with lower monthly premiums, in exchange for cost sharing.

Plan N helps cover hospital coinsurance (including up to 365 additional hospital days), skilled nursing facility coinsurance, hospice care coinsurance, the first three pints of blood, and the 20% Part B coinsurance after the Part B deductible is met.  

To keep premiums lower, it includes small copays for some doctor visits and emergency room visits that do not result in hospital admission.

Plan N does not cover Part B excess charges, which may apply if a provider does not accept Medicare assignment. Because of this, Plan N is often a good fit for people who don’t visit the doctor frequently, typically see Medicare‑accepting providers, and want lower premiums while still having strong coverage.

Choosing the Right Plan

There is no single “best” Medicare Supplement plan. The right choice depends on how often you use medical services, how comfortable you are with cost sharing, and how important predictable expenses are to you.

Some people want maximum coverage with minimal surprises. Others prefer lower premiums and don’t mind paying small amounts as care is needed. Both approaches can work well. It’s all about what gives you peace of mind.

Conclusion

Medicare Supplement plans can look confusing at first, but once you understand what each letter stands for, the decision becomes much clearer. Each plan simply represents a different balance between premiums and out‑of‑pocket costs.

Taking the time to understand these options now can make your Medicare years far less stressful and far more predictable.