The ABCs (and Ds) of Medicare

The first thing that’s important for anyone enrolling in Medicare to understand is that Medicare actually actually refers to four different programs: Part A, B, C and D.

Part A coverage is free for qualifying seniors and pays for inpatient hospital care, skilled nursing care, hospice care and some home health care.

Seniors may also choose to purchase a supplemental Part B Medicare plan, which covers some expenses Part A doesn’t, like doctor visits, outpatient hospital care, durable medical equipment and some other medical services.

Individuals who are entitled to Part A and enrolled in Part B are eligible to switch to Part C, or Medicare Advantage, a group of private health plans that offer the same benefits as Part A and B.

Medicare Part D is a prescription drug benefit seniors can purchase to make their prescription requirements more affordable.

Medicare Part A

Part A Medicare benefits will pay at least some amount on most hospital services in the United States. That includes:

  • A semi-private room (or a private room if it’s medically necessary or if a semi-private room isn’t available)
  • Special care units (like intensive care and coronary care)
  • Operating room charges
  • Nursing services (though not private-duty nursing)
  • Drugs, supplies and appliances provided in and by the hospital
  • Special treatments (like radiation and chemotherapy)
  • Lab and diagnostic tests (like X-rays and CAT scans)
  • Rehabilitation (physical, speech and occupational therapy)

Part A coverage does require that the service is medically necessary and must be performed in an inpatient setting.

Because Part A coverage has a deductible associated with each hospital stay, seniors should be aware that they may be responsible for a portion of any inpatient treatment bill. As of 2018, everyone with Part A pays a deductible of $1,156 for each period of hospitalization and copayments for each day past the first 60 days of a particular hospital stay.

Many seniors purchase private Medicare supplement plans, which may cover some of the costs left over after Medicare pays.

Most enrollees pay no premium, as long as they worked and paid Social Security and Medicare taxes for at least 10 years. If not, they may still buy into Part A coverage for a monthly premium of up to $422.
Medicare Part A is run directly by the federal government’s Centers for Medicare and Medicaid Services (CMS), part of the Department of Health and Human Services. Its website provides information about Medicare Part A, and staffers answer questions by phone at the toll-free number, 800-633-4227.

For more information, visit our Guide to Medicare Part A.

Medicare Part B

Part B is optional coverage that must be purchased. Every citizen and legal resident over 65 is eligible.

Doctor bills are probably the biggest chunk of outpatient expenses that are covered. The category includes any service by a doctor wherever it’s provided — whether that’s a hospital, doctor’s office or clinic. It also covers any other work performed by the doctor’s staff, as well as any drugs administered in the office.

Other services covered by Part B include:

  • Limited chiropractic care
  • Emergency care at an outpatient or urgent care clinic
  • X-rays
  • Lab work
  • Ambulance service
  • Medical equipment and supplies, such as wheelchairs, walkers, diabetic supplies and pacemakers
  • Physical and speech therapy

For services to be covered, they must be ordered by a physician and be deemed medically necessary. They must also be provided by a doctor’s office or other provider that accepts Medicare and is approved by Medicare.

The monthly premium for Part B coverage is at least $134 (more for people with higher incomes) and is automatically deducted from Social Security checks. The program also has an annual deductible of $183. After the deductible, Medicare pays 80 percent of the approved amount for covered doctor services and 80 to 100 percent of the approved amount for outpatient services and medical equipment.

Timing is of the essence: If a potential enrollee waits until more than three months after their 65th birthday to enroll in Part B, they may not enroll until January 1 of the following year, and the coverage won’t start until July 1 of that year.

Medicare’s website has information about Part B eligibility, coverage and enrollment. You can also call Medicare’s toll-free phone number, (800)-MEDICARE (633-4227). Part B’s day-to-day operations, however, are handled by large private insurance companies called Medicare Part B “carriers.”

For more information, visit our Guide to Medicare Part B.

Medicare Part C

A Medicare Part C (also called Medicare Advantage) plan is a private insurance policy that replaces Medicare Part A and Part B. If you enroll in a private Medicare Part C plan, you no longer receive coverage through Medicare Part A or Medicare Part B.

Medicare Part C plans are regulated by the federal government, which requires every plan to provide at least the same coverage as the government-run Medicare Parts A and B. Medicare Part C plans eliminate some Medicare co-payments and deductibles and may provide additional benefits, making them attractive to some seniors.

If a potential enrollee doesn’t enroll in Part C or D when they turn 65, or if they want to switch coverage under Part C or D, they can do so during Medicare’s annual enrollment period, which falls between October 15 and December 7. (Some managed care plans and insurance companies also allow enrollment throughout the year.)

The official Medicare website has a feature called the Medicare Personal Plan Finder that can direct you to Medicare Part C plans available where you live. It also gives information about each plan’s general terms.

For more information, visit our Guide to Medicare Part C.

Medicare Part D

Part D is a collection of private plans that cover prescription drugs. The federal government sets the basic rules for the plans, but they are issued by private insurance companies.

Every prescription drug plan under Part D has different premiums, copayments and drugs it covers. In choosing a plan, be sure not to focus solely on the lowest monthly premium and consider whether it covers the specific drugs needed and what type of copayments might apply. Different plans are offered in every state.

Medicare’s website has information about Part D drug plans available where you live, including the medications currently in each plan’s formulary. Or you can contact Medicare by phone at (800) 633-4227. You can get free, independent expert help in choosing a plan from your local State Health Insurance Assistance Program (SHIP). You can also get independent help online from the Medicare Rights Center.

For more information, visit

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