Medigap is supplemental insurance plan sold by private companies to help cover original Medicare costs, such as deductibles, copayments, and coinsurance. Medicare Supplement Plan M (Medigap Plan M) is one option you can choose for additional coverage.

To be eligible for Medicare Supplement Plan M, you must be enrolled in original Medicare Part A and Part B. You must also live within an area where this plan is sold by an insurance company.

Keep reading to learn more about this option, including what it covers, who’s eligible, and when you can enroll.

Private health insurance companies sell Medicare supplement plans to help reduce out-of-pocket expenses and sometimes pay for services that Medicare doesn’t cover. People also call these Medigap plans.

The federal government requires private insurance companies to standardize Medigap plans. Exceptions exist for Massachusetts, Minnesota, and Wisconsin, who standardize their plans differently.

Most companies name the plans by uppercase letters A, B, C, D, F, G, K, L, M, and N.

Medicare Supplement Plan M (Medigap Plan M) is one of the newer Medigap plan options. This plan is designed for people who want to pay a lower monthly rate (premium) in exchange for paying for half of the annual Part A (hospital) deductible.

Medigap policies are only available to those who have original Medicare, which is Medicare Part A and Part B. If you have Medicare Advantage, you can’t have a Medigap plan as well.

Medicare Supplement Plan M coverage includes the following:

  • 100 percent of Part A coinsurance and hospital costs up to an additional 365 days after Medicare benefits are used up
  • 50 percent of the Part A deductible
  • 100 percent of Part A hospice care coinsurance or copayments
  • 100 percent of costs for blood transfusions (first 3 pints)
  • 100 percent of skilled nursing facility care coinsurance
  • 100 percent of Part B coinsurance or copayments
  • 80 percent of qualifying healthcare costs while traveling abroad

Because Medigap Plan M offers the same coverage no matter what insurance company offers the plan, the main difference is cost. Insurance companies don’t offer the plans at the same monthly premium, so it makes sense to shop around for the lowest-cost policy.

There are lots of factors that go into what an insurance company charges for Plan M. These include:

  • your age
  • your overall health
  • what ZIP code you live in
  • if the insurance company offers discounts for certain factors, such as being a nonsmoker or paying yearly instead of monthly

Once you choose a Medicare supplement plan, the deductibles can increase on a yearly basis. However, some people find it hard to change their coverage because they get older (and premiums are more likely to be higher) and they may find switching plans costs them more.

Other out-of-pocket costs

Before selecting doctor, check if accept the Medicare assigned rates (price Medicare will approve for the procedure and treatment).

If your doctor does not accept Medicare’s assigned rates, you can either find another doctor who will or stay with your current doctor. If you elect to stay, your doctor is not allowed to charge more than 15 percent above the Medicare-approved amount.

The amount charged by your doctor above the Medicare assigned rate is called a Part B excess charge. With Medigap Plan M, you’re responsible for paying Part B excess charges out of pocket..


After you’ve received treatment at the Medicare-approved rate:

  1. Medicare Part A or B pays its share of the charges.
  2. Your Medigap policy pays its share of the charges.
  3. You pay your share of the charges (if any).

Medicare Supplement Plan M is designed for those who want to pay a lower monthly rate in exchange for paying for half of the annual Part A deductible and all of the usual Part B deductible.

If you don’t expect frequent hospital visits and are comfortable with cost-sharing, Medicare Supplement Plan M may be a good choice for you.

Medicare supplement (Medigap) plans help cover some of the “gaps” between the cost of healthcare and what Medicare contributes to those costs.

With Medigap Plan M, you pay a lower premium but share in the costs of your Medicare Part A deductible, Medicare Part B deductible, and Part B excess charges.

Before committing to Medigap Plan M or any other Medigap plan, review your needs with a licensed agent who specializes in Medicare supplements to help you. You can also contact your state’s State Health Insurance Assistance Program (SHIP) for free help in understanding available policies.