Medicare Supplement Plan K: 2026 Coverage and Costs Explained

What Plan K covers (and what it doesn't)

Medigap Plan K is one of the federally standardized Medicare Supplement plans. That means the benefits are set by law and are identical from one insurer to the next — only the premium, the company, and the service differ. What sets Plan K apart from richer plans like Plan G is its cost-sharing design: instead of covering most gaps in full, it splits many of them with you at 50% until you reach an annual ceiling.

Plan K does not cover the Part B deductible ($283 in 2026), Part B excess charges, or foreign travel emergency care. You pay your Original Medicare premiums separately, and Plan K does not include prescription drug coverage — you would add a stand-alone Part D plan for that.

• Part A hospital coinsurance and costs up to an additional 365 days after Medicare benefits end: 100%
• Part A deductible ($1,736 per benefit period in 2026): 50%
• Part B coinsurance or copayment (generally 20% under Original Medicare): 50%
• First 3 pints of blood: 50%
• Part A hospice coinsurance or copayment: 50%
• Skilled nursing facility coinsurance ($217/day for days 21–100 in 2026): 50%
• Part B deductible: not covered
• Part B excess charges: not covered
• Foreign travel emergency: not covered

The $8,000 out-of-pocket limit in 2026

Plan K's defining safety net is its annual out-of-pocket maximum. For 2026, CMS set this limit at $8,000. Once your share of cost-sharing on covered services reaches that amount in a calendar year — and once you've also met the Part B deductible — Plan K pays 100% of covered services for the rest of the year.

This limit is what makes the 50% cost-sharing tolerable: in a catastrophic year, your exposure on Plan-K-covered services is capped rather than open-ended. CMS recalculates the limit each year using an inflation adjustment tied to Medicare per-capita costs, so it generally rises over time. The limit does not include your monthly premiums or anything Plan K doesn't cover, such as the Part B deductible or Part D drug costs.

How your costs add up under Plan K

Because Plan K pays only half of several major charges, it helps to walk through where your dollars go. Under Original Medicare in 2026, the Part A deductible is $1,736 per benefit period and the Part B deductible is $283 per year, after which Part B generally leaves you responsible for 20% coinsurance.

With Plan K, you would pay half of that $1,736 Part A deductible (about $868) if you're hospitalized, and half of your Part B coinsurance on doctor and outpatient services — plus the full Part B deductible, which Plan K never covers. Those 50% shares count toward the $8,000 limit. Healthy years with few claims keep your costs low; a serious illness pushes you toward the cap, where Plan K then takes over fully.

• You still pay the full Part B premium — $202.90/month in 2026 — directly to Medicare.
• You pay the full Part B deductible of $283 before Part B coverage begins; Plan K does not reimburse it.
• Your 50% shares of covered gaps accumulate toward the $8,000 ceiling.
• Premiums you pay for the Plan K policy itself do not count toward the out-of-pocket limit.

What Plan K premiums look like

Plan K premiums are not standardized — only the benefits are. Each insurer sets its own price, and rates vary by your state, age, gender, tobacco use, and the pricing method the company uses (community-rated, issue-age, or attained-age). Because Plan K shifts more cost onto you than plans like G or N, its monthly premium is typically lower than those richer plans.

The trade-off is straightforward: you accept higher potential out-of-pocket cost-sharing in exchange for a smaller monthly bill. To compare actual prices, get quotes from multiple carriers for the identical Plan K benefit set in your ZIP code, since the coverage is the same but the premium is not. Whether Plan K saves you money overall depends on how much care you expect to use.

Who Plan K tends to fit

Plan K can appeal to people who are relatively healthy, want a lower monthly premium, and are comfortable self-insuring part of the risk up to a known annual cap. The $8,000 ceiling provides a backstop against a catastrophic year, which some buyers value more than first-dollar coverage.

It may be a weaker fit if you expect frequent care or want predictable, minimal cost-sharing — in those cases a plan that covers more gaps in full may cost less over a year despite a higher premium. The best choice is individual and depends on your health, budget, and risk tolerance. It's worth comparing Plan K against Plan G, Plan N, and Plan L before deciding.