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Original Medicare (Part A and B) Eligibility and Enrollment

Medicare and Minimum Essential Coverage (MEC)

Medicare Part A counts as minimum essential coverage and satisfies the law that requires people to have health coverage. For additional information about minimum essential coverage (MEC) for people with Medicare, go to our Medicare & Marketplace page.


Medicare Part A and Part B Eligibility and Enrollment

This page contains information on Medicare Part A and Medicare Part B eligibility and enrollment.  For more information about Medicare for people who are still working, go to our Employer Page or I’m 65 and Still Working page. 

We are continuing to improve this page, check back to see new improvements.

Medicare Part A (Hospital Insurance) and Medicare Part B (Medical Insurance) are available to the individuals below:

  • Age 65 or older  
  • Disabled
  • End-Stage Renal Disease (ESRD)

 

Medicare Part A (Hospital Insurance)

Most people get Part A for free, but some have to pay a premium for this coverage.

To be eligible for premium-free Part A, an individual must be entitled to receive Medicare based on their own earnings or those of a spouse, parent, or child. To receive premium-free Part A, the worker must have a specified number of quarters of coverage (QCs) and file an application for Social Security or Railroad Retirement Board (RRB) benefits. The exact number of QCs required is dependent on whether the person is filing for Part A on the basis of age, disability, or End Stage Renal Disease (ESRD). QCs are earned through payment of payroll taxes under the Federal Insurance Contributions Act (FICA) during the person's working years. Most individuals pay the full FICA tax so the QCs they earn can be used to meet the requirements for both monthly Social Security benefits and premium-free Part A.

NOTE: Certain Federal, State, and local government employees pay only the Part A portion of the FICA tax. The QCs they earn can be used only to meet the requirements for premium-free Part A; they may not be used to meet the requirements for monthly Social Security benefits.

To be eligible for premium Part A, an individual must be age 65 or older and be enrolled in Part B. Enrollment in premium Part A and Part B can only happen at certain times. (The section titled Enrollment Periods and When Coverage Begins explains the times when someone can enroll).

More Information on Enrolling in Part A

Individuals already receiving Social Security or RRB benefits at least 4 months before being eligible for Medicare and residing in the United States (except residents of Puerto Rico) are automatically enrolled in both premium-free Part A and Part B. People living in Puerto Rico who are eligible for automatic enrollment are only enrolled in premium-free Part A.

Individuals who are not receiving a Social Security or RRB benefit are not automatically enrolled. These individuals must apply by contacting Social Security.

 

Medicare Part B (Medical Insurance)

The eligibility rules for Part B depend on whether a person is eligible for premium-free Part A or whether the individual has to pay a premium for Part A coverage.

Individuals who are eligible for premium-free Part A are also eligible for enroll in Part B once they are entitled to Part A.  Enrollment in Part B can only happen at certain times.

Individuals who must pay a premium for Part A must meet the following requirements to enroll in Part B:

  • Be age 65 or older;
  • Be a U.S. resident; AND
  • Be either a U.S. citizen, OR
  • Be an alien who has been lawfully admitted for permanent residence and has been residing in the United States for 5 continuous years prior to the month of filing an application for Medicare.

NOTE: Part B is a voluntary program which requires the payment of a monthly premium for all months of coverage.

More Information on Enrolling in Part B

Individuals already receiving Social Security or RRB benefits at least 4 months before being eligible for Medicare and residing in the United States (except residents of Puerto Rico) are automatically enrolled in both premium-free Part A and Part B. People who are automatically enrolled have the choice whether they want to keep or refuse Part B coverage. People living in Puerto Rico who are eligible for automatic enrollment are only enrolled in premium-free Part A; they must actively enroll in Part B to get this coverage.

Individuals who are not receiving a Social Security or RRB benefit are not automatically enrolled. Individuals who previously refused Part B, or who terminated their Part B enrollment, may enroll (or re-enroll) in Part B only during certain enrollment periods. In most cases, if someone does not enroll in Medicare Part B (Medical Insurance) when first eligible, they will have to pay a late enrollment penalty for as long as they have Part B.

 

Understanding the Rules for People Age 65 or Older

To be eligible for premium-free Part A on the basis of age:

  • A person must be age 65 or older; and
  • Be eligible for monthly Social Security or Railroad Retirement Board (RRB) cash benefits.

An individual who is receiving monthly Social Security or RRB benefits at least 4 months prior to turning age 65 does not need to file a separate application to become entitled to premium-free Part A.  In this case, the individual will get Part A automatically at age 65. 

An individual who is not receiving monthly Social Security or RRB benefits must file an application for Medicare by contacting the Social Security Administration.

Part A coverage begins the month the individual turns age 65, provided he or she files an application for Part A (or for Social Security or RRB benefits) within 6 months of the month in which he or she becomes age 65. If the application is filed more than 6 months after turning age 65, Part A coverage will be retroactive for 6 months.

NOTE: For an individual whose 65th birthday is on the first day of the month, Part A coverage begins on the first day of the month preceding their birth month. For example, if an individual's birthday is on December 1, Part A begins on November 1.

More Information for People Age 65 or Older who Must Pay a Premium for Part A

People who must pay a premium for Part A do not automatically get Medicare when they turn 65. They must:

  • File an application to enroll by contacting the Social Security Administration;
  • Enroll during a valid enrollment period; and
  • Also enroll in or already have Part B. 

To keep premium Part A, the person must continue to pay all monthly premiums and stay enrolled in Part B. This means that the person must pay both the premiums for Part B and premium Part A timely to keep this coverage.   

Premium Part A coverage begins prospectively, based on the enrollment period the person uses to apply for coverage.

 

Medicare Based on Disability

A person who is entitled to monthly Social Security or Railroad Retirement Board (RRB) benefits on the basis of disability is automatically entitled to Part A after receiving disability benefits for 24 months. Disabled Federal, State and local government employees who are not eligible for monthly Social Security or RRB benefits may get deemed entitlement to disability benefits and automatically entitled to Part A after being disabled for 29 months.

Special Rule for People with Amyotrophic Lateral Sclerosis (ALS) (Lou Gehrig’s disease)

Individuals whose disability is Amyotrophic Lateral Sclerosis (ALS) are entitled to Part A the first month they are entitled to Social Security or RRB disability cash benefits. There is no waiting period.

Special Rule for People Claiming Child Disability Benefits: SSA rules do not allow for child disability benefit to begin earlier than age 18. Therefore, Part A entitlement based on child disability benefit entitlement can never begin before the month the person attains age 20 (or age 18 if the individual’s disability is ALS).

 

Medicare Based on End-Stage Renal Disease (ESRD)

Individuals are eligible for premium-free Part A if they receive regular dialysis treatments or a kidney transplant, have filed an application for Medicare, and meet 1 of the following conditions:

  • Have worked the required amount of time under Social Security, the Railroad Retirement Board (RRB), or as a government employee; or
  • Are getting or are eligible for Social Security or RRB benefits; or
  • Are the spouse or dependent child of a person who has worked the required amount of time under Social Security, the RRB, or as a government employee; or are getting Social Security or RRB benefits.

Part A coverage begins:

  • The 3rd month after the month in which a regular course of dialysis begins; or
  • The first month a regular course of dialysis begins if the individual engages in self-dialysis training; or
  • The month of kidney transplant; or
  • Two months prior to the month of transplant if the individual was hospitalized during those months in preparation for the transplant.

 

Enrollment Periods and When Coverage Begins

Individuals eligible for premium-free Part A can enroll in Part A at any time after they are first eligible for the coverage.

Individuals who want premium Part A, Part B or both may only enroll during certain enrollment periods that are outlined in law. The following enrollment periods apply to both premium Part A and Part B:

  • Initial enrollment period
  • General enrollment period, and
  • Special enrollment period for the working aged, the working disabled, and international volunteers

Initial Enrollment Period (IEP)

The IEP is a 7-month period that begins 3 months before the month a person turns 65 and ends 3 months after the person turns 65. For someone under age 65 who becomes entitled to Medicare based on disability, entitlement begins with the 25th month of disability benefit entitlement. For these individuals, the IEP begins 3 months before the 25th month of disability benefit entitlement, includes the 25th month, and ends three months after. The IEP for people with ESRD and ALS varies based on their situation.

Coverage begins based on when you enroll during the IEP.  If a person enrolls in the first 3 months of the IEP, coverage begins the first month the person is eligible for Medicare. If a person enrolls in any other month of the IEP, coverage will be delayed. Disabled individuals are automatically enrolled in Medicare Part A and Part B after they have received disability benefits from Social Security for 24 months.

NOTE: In most cases, if someone does not enroll in Part B or premium Part A when first eligible, they will have to pay a late enrollment penalty. The Part B penalty is assessed for as long as the person has Part B. 

General Enrollment Period (GEP)

The GEP takes place from January 1 through March 31 of each year. Part B and Premium Part A coverage begins July 1 of that same year.

Special Enrollment Period (SEP) for the Working Aged and Working Disabled.

Individuals who do not enroll in Part B or premium Part A when first eligible because they were covered under a group health plan based on their own or a spouse's current employment (or the current employment of a family member, if disabled) may enroll during the SEP. The individual can enroll at any time while covered under the group health plan based on current employment, or during the 8-month period that begins the month the employment ends or the group health plan coverage ends, whichever comes first.

NOTE: Individuals with ESRD are not eligible to enroll during the SEP.

Special Enrollment Period (SEP) for International Volunteers

Individuals who do not enroll in Part B or premium Part A when first eligible because they were performing volunteer service outside of the United States for at least 12 months on behalf of a tax-exempt organization and had health insurance that provided coverage for the duration of the volunteer service may enroll during this SEP.

Policy for when enrollment for volunteers can occur

The SEP for volunteers is the 6-month period that begins the earlier of the first day of the month following the month for which the:

  • individual was no longer serving as a volunteer outside of the United States;
  • organization no longer has tax-exempt status; or
  • individual no longer has health insurance that provides coverage outside of the United States.

NOTE: Enrollment in Part B or premium Part A may not occur prior to the end of the IEP.

 

Termination of Enrollment

Individuals entitled to premium-free Part A cannot voluntarily terminate their Part A coverage. This is not permitted by law. Generally, premium-free Part A ends due to:

  • Loss of entitlement to Social Security or Railroad Retirement Board benefits; or
  • Death.

There are special rules for when premium-free Part A ends for people with ESRD.

Premium Part A and Part B coverage can be voluntarily terminated because premium payments are required. Premium Part A and Part B coverage ends due to:

    • Voluntary disenrollment request (coverage ends prospectively);
    • Failure to pay premiums;
    • For individuals under age 65 (disabled and ESRD), because their Part A entitlement ended (Part B terminates at the same time as Part A); or
    • Death.

 

Premiums

Premium Part A and Part B coverage requires payment of monthly premiums.

IRMAA (Income-Related Monthly Adjustment Amount)

Individuals with income greater than $85,000 and married couples with income greater than $170,000 must pay a higher premium for Part B and an extra amount for Part D coverage in addition to their Part D plan premium. This additional amount is called income-related monthly adjustment amount. Less than 5 percent of people with Medicare are affected, so most people will not pay a higher premium. 

Late enrollment penalty for premium Part A

If an individual did not enroll in premium Part A when first eligible, they may have to pay a higher monthly premium if they decide to enroll later.  The monthly premium for Part A may increase up to 10%. The individual will have to pay the higher premium for twice the number of years the individual could have had Part A, but did not sign up.

Example: If an individual were eligible for Part A for 2 years but did not sign-up, the individual will have to pay the higher premium for 4 years.

Late enrollment penalty for Part B

If an individual did not sign up for Part B when first eligible, the individual may have to pay a late enrollment penalty for as long as the individual has Medicare. The individual’s monthly premium for Part B may go up 10% for each full 12-month period that the individual could have had Part B, but did  not sign up for it.

Example: Ms. Green’s Initial Enrollment Period ended September 30, 2009. She did not decide to enroll in Part B until the General Enrollment Period in March 2013. Ms. Green’s Part B penalty is 20%. (While Ms. Green waited a total of 30 months to sign up, this included only 2 full 12-month periods.)

NOTE: Usually an individual does not pay a penalty if the individual can meet certain conditions that allow the individual to sign up for Part A and/or Part B during a SEP.