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Medicare Overview

Medicare is a government-funded health insurance program. It covers people age 65 or older, some younger people (including children) with disabilities and those who have been getting Social Security disability benefits (SSI or SSDI) for 2 years. People who have Medicare are called Medicare beneficiaries.

The Medicare parts

Medicare parts cover different services:

  • Part A covers most hospitalization and inpatient expenses. It also covers skilled nursing facility care, hospice care, and home health care. Most people do not have to pay for Part A premiums, but will have to pay premiums for Part B and Part D of Medicare. Beneficiaries with higher incomes will have to pay higher premiums.
  • Part B covers medically needed care such as doctor visits, outpatient care, home health care, medical equipment, some services to prevent disease, and certain screening tests used to help find diseases early.
  • Part C refers to the optional Medicare Advantage Plans offered by private companies approved by Medicare. If you choose one of these alternative plans, it will provide all of your Part A and Part B coverage. Most include Part D coverage, too. Some Medicare Advantage Plans also offer extra coverage, such as vision, hearing, dental, and/or health and wellness programs.
  • Part D is optional. It covers your prescription drugs and you enroll in it by choosing one of the Medicare Prescription Drug Plans. Most Medicare Advantage plans cover prescription drugs, but if yours doesn’t, you may still choose a Part D Prescription Drug Plan.

Does the doctor take Medicare and accept assignment?

Before you schedule any appointments or tests, be sure that the doctor accepts Medicare, and find out if they “accept assignment.” A doctor who accepts assignment is called a participating doctor, and will:

  • Take the amount Medicare pays, along with your standard deductible and co-pay, as payment in full.
  • Usually wait for Medicare to pay for their share before asking for your payment.
  • Likely cost you less in “out-of-pocket” charges (the amount you must pay).
  • Send your claims to Medicare and not charge you for submitting the claim.
  • Not require you to pay a deductible and co-pay for many preventive services. (These are discussed below.)

Non-participating doctors don’t routinely take assignment. If your doctor doesn’t accept assignment for all Medicare-covered services, you often have to pay out of pocket, and you can be charged more than Medicare covers. Medicare will pay you back part of the bill for the services they cover.

Opt-out doctors have opted out of Medicare and will ask you to sign a private contract explaining that Medicare won’t pay anything to you or the doctor. You’re responsible for all charges if you see these doctors.

For more detailed information on Medicare eligibility, costs, and coverage, contact the Centers for Medicare & Medicaid Services (CMS) at 1-800-MEDICARE (1-800-633-4227) or visit their website at

Coordination of benefits

Some people covered by Medicare may also have other health insurance. These might include coverage through an employer (own or spouse’s), other federal programs, or because of an injury. People may also be eligible for both Medicare and Medicaid. In these situations, there may be questions about coordination of benefits (which insurance pays first and for which part of the bill). Each situation is different, so for questions check

Getting help paying for Medicare

You might be able to get help with the costs of your Medicare coverage through Medicare savings programs.

Some states have programs that can help you pay for Medicare premiums, deductibles, and co-pays. These programs help people with Medicare who have low incomes and limited resources. The names of the programs and how they work vary from state to state. To find out more about these programs and to see if you qualify, visit Medicare Savings Programs .

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The Official U.S. Government Site for Medicare
Toll-free number:  1-800-MEDICARE (1-800-633-4227)

This is a federal government website managed by the U.S. Centers for Medicare and Medicaid Services.  It provides information about what Medicare covers, drug coverage (Part D), how to find a doctor or facility, and additional resources.

Centers for Medicare and Medicaid Services (CMS).  What's Medicare? Accessed at on April 19, 2019.

Centers for Medicare and Medicaid Services (CMS).  Medicare savings programs.  Accessed at on April 19, 2019.

Centers for Medicare and Medicaid Services (CMS). Find Medicare physicians and other clinicians.  Accessed at on April 19, 2019.

Last Revised: May 13, 2019