Plan K
Cost-sharing plan with a federal annual out-of-pocket limit
Plan K pays 50% of Part B coinsurance, blood (first 3 pints), Part A hospice coinsurance, skilled nursing facility coinsurance, and the Part A deductible. Once the annual out-of-pocket limit (published by CMS each year) is met, Plan K pays 100% of covered services for the rest of the calendar year. It does not cover the Part B deductible, Part B excess charges, or foreign travel emergency.
Coverage of the 10 federal benefits
- 2 · Fully covered
- 5 · 50% covered
- 3 · Not covered
What Plan K covers (federal CMS standardization)
The covered-benefits matrix below is verbatim from medicare.gov. Every cell is federally frozen by the 1990 NAIC Medicare Supplement Standardization Act.
- Part A coinsurance and hospital costs (up to an additional 365 days after Medicare benefits are used up)Covered ✓
- Part B coinsurance or copayment50%
- Blood (first 3 pints)50%
- Part A hospice care coinsurance or copayment50%
- Skilled nursing facility care coinsurance50%
- Part A deductible50%
- Part B deductibleNot covered
- Part B excess chargesNot covered
- Foreign travel emergency (up to plan limits)Not covered
- Out-of-pocket limit (applies to Plans K and L only)Covered ✓¹
¹ Plans K and L include an annual out-of-pocket limit. After the limit is met for the calendar year, Plan K (or L) pays 100% of covered services for the remainder of the year. For 2026, the Plan K limit is $8,000 and the Plan L limit is $4,000 (per CMS K & L Out-of-Pocket Limits Announcement, October 2025; statutory basis 42 U.S.C. § 1395ss(w)(2)).
State availability
Plan K is part of the federal 10-letter Medigap system. Massachusetts, Minnesota, and Wisconsindo not use the federal letter system — if you live in those states, your Medigap plan structure is different. See your state page:
When can you buy Plan K?
During your federal 6-month Medigap Open Enrollment Period (per 42 U.S.C. § 1395ss), every insurer that offers Plan K in your state must issue you a policy regardless of your health status. Outside that window, in most states, insurers may medically underwrite, deny, or surcharge .
Compare Plan K side-by-side
The full federal benefits matrix with Plan K highlighted:
| Benefit | A | B | CMACRA grandfathered | D | FMACRA grandfathered | G | K | L | M | N |
|---|---|---|---|---|---|---|---|---|---|---|
| Part A coinsurance and hospital costs (up to an additional 365 days after Medicare benefits are used up) | ||||||||||
| Part B coinsurance or copayment | 50% | 75% | See note | |||||||
| Blood (first 3 pints) | 50% | 75% | ||||||||
| Part A hospice care coinsurance or copayment | 50% | 75% | ||||||||
| Skilled nursing facility care coinsurance | 50% | 75% | ||||||||
| Part A deductible | 50% | 75% | 50% | |||||||
| Part B deductible | ||||||||||
| Part B excess charges | ||||||||||
| Foreign travel emergency (up to plan limits) | ||||||||||
| Out-of-pocket limit (applies to Plans K and L only) |
Reading the matrix: ✓ = the plan covers 100% of the federally-defined benefit; 50%/75% = the plan pays that share of the benefit; ✗ = the plan does not cover the benefit. Plans C and F are closed to people newly eligible for Medicare on or after 2020-01-01 per MACRA 2015 grandfathering. Massachusetts, Minnesota, and Wisconsin do not use the federal 10-letter system; see your state page for the state-specific Medigap structure.
Plan footnotes
- 1. Plan K · Out-of-pocket limit (applies to Plans K and L only): Plans K and L include an annual out-of-pocket limit. After the limit is met for the calendar year, Plan K (or L) pays 100% of covered services for the remainder of the year. For 2026, the Plan K limit is $8,000 and the Plan L limit is $4,000 (per CMS K & L Out-of-Pocket Limits Announcement, October 2025; statutory basis 42 U.S.C. § 1395ss(w)(2)).