Medigap Plan K vs Plan L: Cost-Sharing Plans Explained

What Are Medicare Supplement Plans K and L?

Medicare Supplement (Medigap) Plans K and L are two of the ten federally standardized Medigap plan letters, and they are the only two designed around a cost-sharing structure. Instead of paying nearly all of your Medicare gap costs like Plan G or Plan F, they pay a fixed percentage (50% for Plan K, 75% for Plan L) of certain expenses. In return, they charge lower monthly premiums and add something Original Medicare does not have on its own: a hard annual out-of-pocket maximum.

Once you meet that yearly cap and the Part B deductible ($283 in 2026), the plan pays 100% of Medicare-covered services for the rest of the calendar year. That combination of lower premiums and a capped downside is what makes them worth a serious look, especially if you are healthy. For a broader view of how these fit alongside the other lettered plans, see our full Medigap plan comparison.

Plans K and L are available in most states, though Massachusetts, Minnesota, and Wisconsin use their own non-standardized Medigap structures and do not sell K or L by those names.

What Plan K and Plan L Actually Cover

All standardized Medigap plans must cover the same list of benefits. What changes is how much of each benefit they cover. Plan K pays 50% of a defined set of shared costs, and Plan L pays 75% of that same set. Both plans pay 100% of Part A hospital coinsurance plus 365 additional hospital days after Medicare benefits are exhausted.

Here is the side-by-side breakdown for 2026:

Neither plan covers the Part B deductible, Part B excess charges, or foreign travel emergency care. If you travel abroad often or live in a state where doctors can bill above Medicare-approved amounts, that trade-off matters. To see how excess charges work and which states ban them, our guide to gaps Medigap fills is a good starting point.

How the out-of-pocket cap works

The out-of-pocket cap only counts what you pay toward Medicare-approved services that the plan cost-shares on. Once you have paid $8,000 (Plan K) or $4,000 (Plan L) and you have met the Part B deductible, your Medigap plan flips to 100% coverage for covered services for the remainder of the year. This is a feature Plans G and N do not have because they cover so much upfront that a cap is unnecessary.

Plan K vs Plan L: A Direct Comparison

The easiest way to think about Plan K vs Plan L is this: Plan L costs more per month, but you reach the "everything paid" point twice as fast if you have a bad health year.

Because Plan L pays a higher share of every cost-sharing item, it also protects you sooner. If you ended up with a hospital stay and a rough recovery, hitting a $4,000 cap on Plan L is much less painful than hitting an $8,000 cap on Plan K.

How Much Do Plan K and Plan L Cost in 2026?

Medigap premiums are not standardized. Each carrier sets its own rates based on your state, ZIP code, age, gender, tobacco use, and pricing method (community-rated, issue-age, or attained-age). But across the market, Plans K and L are consistently the two cheapest lettered plans on the shelf.

Typical 2026 monthly premium ranges (age 65, non-smoker):

For context, our 2026 Medicare Supplement cost guide shows the national average Plan G premium is around $166 at age 65 and Plan N averages about $123. Plan K commonly comes in $60 to $100 per month cheaper than Plan G in the same market. Over a full year, that is $720 to $1,200 in premium savings that you can reserve for potential cost-sharing.

State rate filings back this up. In New York, for example, Plan K premiums typically run between roughly $97 and $146 across regions, while Plan L runs from about $200 to $287 depending on carrier and area.

Comparing K and L to Plan G and Plan N

Plan G is far more comprehensive: after the $283 Part B deductible, it pays essentially all Medicare cost-sharing. Plan N sits in the middle, with small copays for office visits and ER trips. For a full breakdown of Plan N's copay structure, see our Plan N deep dive, and for how Plan G stacks up, our Plan G coverage guide has the details.

Which Carriers Still Sell Plan K and Plan L?

Not every Medigap carrier bothers with K and L because demand is thin. But several major national insurers still write these plans in most states:

• AARP / UnitedHealthcare offers both Plan K and Plan L in many markets. See our full AARP Medicare Supplement review for pricing and rating details.
• Humana actively sells Plan K and Plan L on an individual basis in numerous states. Details on their lineup and discounts are in our Humana Medigap review.
• Mutual of Omaha offers Plan K in select states.
• Transamerica sells Plan L (but not Plan K) in some states.
• Cigna / HealthSpring (HCSC) and several regional Blue Cross Blue Shield affiliates offer K and/or L in specific states.

Who Should Actually Choose Plan K or Plan L?

Plans K and L are not for everyone. In fact, according to KFF, Plan G alone accounts for about 39% of Medigap enrollment, while K and L together are a small fraction of the market. That is partly because most Medigap buyers value predictability over savings.

Ideal candidates for Plan K or Plan L

• Healthy retirees who rarely see specialists and take few prescriptions
• Budget-conscious enrollees who want a Medigap plan but cannot stomach $180+ monthly premiums
• People with strong savings who could comfortably absorb the $4,000 or $8,000 cap in a bad year
• Seniors weighing Medigap vs. Medicare Advantage who want to stay in Original Medicare but keep premiums close to MA levels. Our Medigap vs. Medicare Advantage guide explains that trade-off in detail.
• Enrollees in states that ban Part B excess charges (CT, MA, MN, NY, OH, PA, RI, VT), where one of the biggest gaps in K and L is legally irrelevant

Who should skip K and L

If you have chronic conditions, take multiple medications, see specialists routinely, or simply want the peace of mind that comes with predictable bills, Plan G or Plan N is a better fit. Someone on the fence between Plan F and Plan G should read our Plan F explainer instead, especially if they were eligible for Medicare before January 1, 2020.

Frequently Asked Questions

Is Medigap Plan K worth it in 2026?

Plan K can be worth it if you are healthy, want the lowest possible Medigap premium, and can comfortably absorb up to $8,000 in cost-sharing during a bad health year. The $8,000 annual out-of-pocket cap gives you catastrophic protection that Original Medicare alone does not offer. For low utilizers, the premium savings often outweigh the cost-sharing risk over multiple years.

What is the difference between Plan K and Plan L?

Plan K pays 50% of certain cost-sharing items with an $8,000 annual out-of-pocket cap in 2026, while Plan L pays 75% of those same items with a $4,000 cap. Plan L has higher monthly premiums but protects you sooner in a bad health year. Both plans cover 100% of Part A hospital coinsurance and add 365 extra hospital days.

Does Plan K or Plan L cover the Part B deductible?

No. Neither Plan K nor Plan L covers the Part B deductible, which is $283 in 2026. You must pay that deductible in full before the plan's out-of-pocket cap logic begins. This is one of the main reasons these plans are cheaper than Plan G, which also does not cover the Part B deductible, or Plan F, which does but is closed to most new enrollees.

Are Plan K and Plan L available in every state?

Plans K and L are standardized Medigap plans in most states, but they are not sold under those letter names in Massachusetts, Minnesota, or Wisconsin, which have their own Medigap structures. Even in states where they are available, not every insurer offers them, so carrier options can be limited. Always check current availability in your ZIP code before enrolling.

Can I switch from Plan G to Plan K or Plan L later?

Yes, but you may face medical underwriting if you are outside your Medigap Open Enrollment Period or a guaranteed-issue window. That means the carrier can review your health history and either charge higher rates or deny coverage. A handful of states have "birthday rules" or year-round guaranteed-issue rights, so check your state's protections before assuming you can freely switch.