\Medigap Plan K is a Medicare Supplement Insurance plan that covers certain out-of-pocket expenses associated with Medicare Part A and Part B coverage. Plan K differs from most other Medigap plan options because it pays only part of the cost of the services it covers, but that reduced coverage also helps keep premium costs down.

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How it works
Medicare Part A and Part B members can buy a Medigap plan to help pay for costs beyond their Original Medicare coverage, including copays, deductibles and coinsurance.

There are 10 standardized Medigap plans available in most states (except Massachusetts, Minnesota and Wisconsin, which use different standards). The plans differ in terms of coverage for services, out-of-pocket limits and premium costs.

Unlike most Medigap plans, Plan K doesn’t pay for 100% of the services it covers. It covers 50% of the cost of most of its covered services, so you would still pay the other 50% out of pocket. However, Plan K is also one of only two Medigap plans with an out-of-pocket limit: in 2023, after you pay $6,940 out of pocket, the plan pays 100% of its covered services for the rest of the year.

What Medigap Plan K covers
Medigap Plan K covers the following, according to Medicare.gov:

Part A coinsurance and hospital costs up to an additional 365 days after Medicare benefits are used up.

Part A deductible (50%).

Part A hospice care coinsurance or copayment (50%).

Part B coinsurance or copayment (50%).

Skilled nursing facility care coinsurance (50%).

Blood transfusion (first three pints) (50%).

Annual out-of-pocket limit of $6,940 in 2023.

What Medigap Plan K doesn’t cover
Here are the benefits Medigap Plan K doesn’t cover that are included in some other plans:

Medicare Part B excess charges (if a provider is permitted to charge more than Medicare’s approved amount and does so).

Emergency care during travel outside the U.S.

Additionally, all Medigap plans, including Plan K, sold to new Medicare members don’t cover the following:

Part B deductible (since 2020, new Medicare members can’t buy any plan that covers the Part B deductible, although existing members may own older plans that do).

Prescription drugs.

Long-term care (like non-skilled care you get in a nursing home).

Dental care.

Vision care.

Private-duty nursing.

How much does Medigap Plan K cost?
Because it covers less than other Medigap options, Plan K has relatively low premiums. This plan is regulated by the federal government but sold by private health insurance companies, which set prices according to factors including age, location and tobacco use. In a representative North Carolina ZIP code (27406), monthly premiums for a 65-year-old nonsmoker range from $47 to $112.

To find out what a Medigap Plan K plan would cost you, visit Medicare.gov.

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Enrolling as soon as possible during your Medigap open enrollment period will get you the best price for Medigap Plan K coverage.

This period happens only once. It starts once you’re 65 and enrolled in Medicare Part B, and lasts for six months. (If you're still working after 65 and covered by a group employer plan that is deemed creditable coverage, your six-month period starts after you’ve ended active employment or no longer have that insurance.)

Medigap policies are cheapest and easiest to get during this open enrollment period because insurance companies aren’t allowed to factor your health or medical history into your price. After the period ends, the prices may go up or you may be denied coverage due to your health status or medical history.

In some states, insurance companies sell Medigap plans to those under 65 who are living with a disability and are eligible for Medicare. You can find more information through your State Health Insurance Assistance Program, or SHIP.

If you have questions about Medicare, visit Medicare.gov or call 800-633-4227 (TTY: 877-486-2048).