Medicare Part A is considered hospital insurance. It covers inpatient stays at:

But who exactly is eligible for Part A? Continue reading as we delve deeper into this part of Medicare and how to know if you’re eligible for coverage.

To meet the basic eligibility requirements, you must be a citizen or permanent resident of the United States and also be one of the following:

To receive coverage under Part A, you must be admitted as an inpatient at the hospital or other treatment center. If you’re not formally admitted as an inpatient, the services received will be considered outpatient care, which is covered under Part B.

Because of this, it’s always important to ask your doctor or caregiver if you’re an inpatient or an outpatient during your stay. Your inpatient or outpatient status can affect how long your stay will be covered and how much you may pay in deductibles and coinsurance costs.

Typically, many people who enroll in Part A are age 65 and older. However, some specific groups of people younger than 65 years old may also be eligible for Part A. These groups include people with:

  • a disability
  • ALS
  • ESRD

Some people will be automatically enrolled in parts A and B, while others will have to sign up. You’ll be automatically enrolled if:

  • You’re already receiving Social Security or Railroad Retirement Board (RRB) benefits. You’ll be automatically enrolled on the first day of the month you turn age 65 if you’ve been receiving these benefits at least 4 months before your birthday.
  • You’re less than 65 years old and have a disability. You’ll be automatically enrolled after receiving Social Security or RRB disability benefits for 24 months.
  • You have ALS. You’ll be automatically enrolled the month that you’re eligible to receive Social Security or RRB disability benefits.

People who aren’t receiving Social Security or RRB benefits or who have ESRD will have to sign up for Medicare. This can be done through the Social Security Administration website.

Below are some important enrollment deadlines related to Medicare parts A and B to keep in mind:

Initial enrollment: Your 65th birthday

If you’re eligible for Medicare parts A and B when you turn 65 years old, initial enrollment consists of a 7-month period that includes:

  • the 3 months before your 65th birthday
  • the month of your 65th birthday
  • the 3 months after your 65th birthday

If you won’t be automatically enrolled in Medicare parts A and B when you turn age 65, you can sign up at any time during initial enrollment. When your coverage starts will depend on when you sign up.

In addition to parts A and B, you can also sign up for a Part D (prescription drug coverage) plan during this time.

General enrollment: January 1 to March 31

During this time, you can sign up for parts A and B if both of the following are true:

  • You didn’t sign up when you were initially eligible (during initial enrollment).
  • You can’t enroll during a special enrollment period.

If you enroll during general enrollment, your coverage will begin on July 1. You’ll have to pay a premium for parts A and B and may also be subject to a late enrollment penalty.

During this time, you can also switch from a Part C (Medicare Advantage) plan back to original Medicare (parts A and B).

Medicare Advantage open enrollment: April 1 to June 30

If you enrolled in Medicare parts A and B for the first time during general enrollment, you can add a Part D plan during this time. Your coverage will begin on July 1.

Open enrollment: October 15 to December 7

During the annual open enrollment period, anyone with Medicare parts A and B can change to a Part C plan or add, switch, or remove a Part D plan. New coverage will begin on January 1.

Special enrollment

If your initial enrollment period has passed, you may be able to sign up for parts A and B during a special enrollment period. You can do this if you’re covered under a group health plan provided by your employer. You can sign up:

  • anytime when you’re covered by the group health plan
  • in the 8 months following the end of employment or the end of coverage by the group health plan

If you can’t receive premium-free Part A, you’ll have to pay a late enrollment penalty if you don’t buy Part A when you’re first eligible. In this case, your monthly premium can go up by 10 percent.

You’ll be subject to this higher premium for double the amount of years that you were eligible but didn’t enroll. For example, if you enroll 1 year after you were eligible, you’ll pay the higher monthly premium for 2 years.

  • Medicare Part A is hospital insurance and is part of original Medicare. Generally speaking, you’re eligible for Part A if you’re age 65 or older, have a disability, or have ESRD or ALS.
  • Some people will be automatically enrolled in Part A, while others will have to sign up.
  • Pay attention to important Medicare deadlines to ensure that you sign up for coverage when you’re eligible.