Medicare Part A Definition

What Is Medicare Part A?

Medicare Part A is one of four components of the federal government’s health insurance program for older adults and other eligible people. Medicare Part A helps pay for bills related to inpatient hospital stays and procedures; inpatient care in a skilled nursing facility; hospice care; and home health care.

It covers expenses such as semi-private rooms at skilled nursing facilities as well as inpatient care, supplies, and drugs during a hospital stay. Physical and occupational therapy in your home if you are homebound is also covered. For terminally ill patients, doctor’s services, medication, and grief-and-loss counseling for the families are covered.

Key Takeaways

  • Medicare Part A pays for care at a hospital, skilled nursing facility, or nursing home, and for home health services.
  • Most people receive Part A for free because they’ve paid the Medicare payroll tax during their working years.
  • If you haven’t started collecting Social Security at age 65, you need to enroll in Medicare online, by phone, or at a Social Security office.
  • Medicare doesn’t cover all services, such as simple custodial care in a nursing home if the patient doesn’t need other types of care. 
  • The CARES Act expanded Medicare's ability to cover COVID-19-related treatment.

Understanding Medicare Part A

Medicare Part A, which is also known as Medicare hospital coverage, pays for care at a hospital, skilled nursing facility, or nursing home, and for home health services. Enrollees who paid Medicare taxes during their working years or people whose spouses paid these taxes don’t pay premiums for Medicare Part A once they’re 65 years old. This means you've already paid your premiums through the 1.45% Medicare payroll tax that you and your employer each paid on all of your wages.

If you didn’t pay this tax during your working years, you do pay premiums—as much as $506 per month in 2023 ($499 for 2022). Younger people who receive long-term Social Security disability benefits also qualify for premium-free Part A. However, even when Medicare Part A is premium-free, most people will still have out-of-pocket expenses for copayments and coinsurance.

People insured under Medicare still have to pay deductibles, too. For 2023, deductibles for inpatient hospital stays are $1,600 ($1,556 for 2022). This payment covers the first 60 days of a patient's stay in the hospital. Copays kick in after the 61st day. Patients are responsible for a $400 copay ($389 for 2022) for the 61st to 90th day in the hospital.

Medicare Part A Eligibility

In general, you're eligible for Medicare Part A if you meet the citizenship and residency requirements and you:

  • Are age 65 or older.
  • Get disability benefits from Social Security or the Railroad Retirement Board for at least 25 months.
  • Get disability benefits because you have amyotrophic lateral sclerosis (ALS), also called Lou Gehrig's disease.
  • Have end-stage renal disease (ESRD) and meet certain requirements.

How to Sign Up for Medicare Part A

Many people are automatically enrolled when they qualify, while others have to sign up for it. In general, it depends on whether you're receiving Social Security benefits. You may, for example, be enrolled automatically in Medicare Part A and Medicare Part B if you:

  • Have received benefits from Social Security or the Railroad Retirement Board for at least four months before you turn 65.
  • Have received Social Security benefits for at least 24 months.
  • Have ALS. You will automatically get Medicare Parts A and B when your disability benefits start.

If you have ESRD, you're eligible for Medicare and can enroll in Parts A and B or in a Medicare Advantage Plan. If you choose Original Medicare (Parts A and B), you will need both parts to get the full benefits available with Medicare to cover certain dialysis and kidney transplant services. If you're interested in a Medicare Advantage Plan, be sure to check that the health care providers you currently see or want to see in the future, are in the plan's network.

If you aren't automatically enrolled in Medicare and you'll be eligible when you turn 65, you should sign up through Social Security during your initial enrollment period. This is a seven-month period that:

  • Starts three months before the month you turn 65.
  • Includes the month you turn 65.
  • Ends three months after the month you turn 65.

Enrollment can be done online, by phone, or at a Social Security office.

In most cases, if you don't enroll in Part B when you first become eligible, you'll owe a late enrollment penalty each month for as long as you have Part B and could have a gap in your health insurance.

Special Considerations for Medicare Part A

Although Medicare Part A covers many hospital-related services, it doesn’t cover everything. Providers must ask patients to sign a notice before receiving treatment when a service may not be covered. This procedure allows the patient to choose whether to accept the service and pay for it out of pocket or to refuse the service.

To be proactive about keeping your medical bills down, it’s a good idea to find out before using a Part A service if Medicare will cover all, part, or none of the cost. If Medicare won’t cover enough of the expense, find out why. There may be an alternative that is covered that would still help you, or you can file an appeal to try to get the coverage decision changed in your favor.

The three reasons why Medicare Part A might not cover something are:

  • General federal and state laws
  • Specific federal laws about what Medicare covers
  • Local Medicare claims processors’ assessment of whether a service is medically necessary

One example of a service Medicare does not usually cover is custodial care in a skilled nursing facility—help with basic activities of daily living, such as getting dressed, bathing, and eating—if it’s the only care you need. You must have more serious medical needs for Medicare to cover your stay at a nursing home.

The CARES Act of 2020

On March 27, 2020, former President Trump signed into law a $2 trillion coronavirus emergency stimulus package called the Coronavirus Aid, Relief, and Economic Security (CARES) Act. It expanded Medicare's ability to cover treatment and services for those affected by COVID-19. The CARES Act also:

  • Increases flexibility for Medicare to cover telehealth services.
  • Authorizes Medicare certification for home health services by physician assistants, nurse practitioners, and certified nurse specialists.
  • Increases Medicare payments for COVID 19–related hospital stays and durable medical equipment.

For Medicaid, the CARES Act clarifies that non-expansion states can use the Medicaid program to cover COVID 19–related services for uninsured adults who would have qualified for Medicaid if the state had chosen to expand. Other populations with limited Medicaid coverage are also eligible for coverage under this state option.

Is Medicare Part A Expensive?

It depends. For most Americans, Part A has no monthly premium because they, or their spouse, paid Medicare taxes throughout their career. If this is not the case, an individual will have a premium of up to $506 per month in 2023 ($499 for 2022). Regardless of premium costs, all individuals with Medicare will be responsible for additional costs like copays, coinsurance, and deductibles.

How Do I Sign Up for Medicare Part A?

For many people, enrollment in Medicare Part A is automatic. This is the case for individuals who have received Social Security or Railroad Retirement Board benefits for at least four months before the age of 65, or at least 24 months. Enrollment is also automatic for anyone diagnosed with Amyotrophic Lateral Sclerosis (ALS), also called Lou Gehrig's disease.

Do I Need Any Other Insurance Besides Medicare Part A?

Yes. Medicare Part A does not include coverage for every medical need. It does cover most costs for care at a hospital, skilled nursing facility, or nursing home, and for home health services. However, you will need coinsurance for other needs like dental, vision, doctor visits, prescription drugs, and more.

Article Sources
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  1. "What Part A Covers."

  2. "Inpatient Hospital Care."

  3. "Skilled Nursing Facility (SNF) Care."

  4. "Home Health Services."

  5. "Hospice Care."

  6. U.S. Congress. "H.R.748 - CARES Act."

  7. Internal Revenue Service. "Topic No. 751 Social Security and Medicare Withholding Rates."

  8. Centers for Medicare & Medicaid Services. “2023 Medicare Parts A & B Premiums and Deductibles 2023 Medicare Part D Income-Related Monthly Adjustment Amounts."

  9. Centers for Medicare & Medicaid Services. "Original Medicare (Part A and B) Eligibility and Enrollment."

  10. Centers for Medicare & Medicaid Services. "Enrolling in Medicare Part A & Part B," Pages 13-17, 21-23, 24.

  11. Social Security Administration. "Medicare Benefits."

  12. "Part B Late Enrollment Penalty."

  13. "Health Care & Prescriptions in a Nursing Home."

  14. "What's Not Covered by Part A & Part B?"

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