What is Medicare Supplement Insurance?

Original Medicare pays for many, but not all, health care services and supplies. Medicare Supplement Insurance Insurance (also called Medigap) is sold by private companies, and can help pay some of the health care costs that Original Medicare doesn't cover, like copayments, coinsurance, and deductibles.

Important facts before you buy

  • You must have Part A and Part B Medicare coverage.
  • You must pay the private insurance company a monthly premium for your Medigap policy in addition to your monthly Part B premium you pay to Medicare.
  • A Medicare Supplement Insurance policy only covers one person. Spouses must buy separate policies.
  • You can't have prescription drug coverage in both your Medicare Supplement Insurance policy and a Medicare drug plan (Part D).
  • It's very important you compare Medicare Supplement Insurance policies since the costs can vary and may go up as you get older.

When to buy

The best time to buy a Medicare Supplement Insurance policy is during your Medicare Supplement Insurance Open Enrollment Period. This 6-month period begins on the first day of the month in which you are 65 or older and enrolled in Part B.

If you delay enrolling in Part B because you have group health coverage based on you (or your spouse's) current employment, your Medicare Supplement Insurance Open Enrollment Period won't start until you sign up for Part B.

Links for more information

Visit Medicare.gov/medicare-and-you to view the "Medicare & You" handbook.

Visit Medicare.gov/publications to view the booklet "Choosing a Medigap Policy: A Guide to Health Insurance for People with Medicare."

Call your State Insurance Department. Visit Medicare.gov/contacts or call 1-800-MEDICARE to get your state department's phone number.

Call your State Health Insurance Assistance Program (SHIP). Visit medicare.gov/contacts to find the phone number and links to your state's program.