Medicare Entitlement for Individuals Under Age 65 – General Overview

March 12, 2026 / 5 min read

A claimant’s Medicare entitlement status is a key factor in determining potential Medicare secondary payer (MSP) compliance obligations. If the claimant is a Medicare beneficiary, this triggers certain potential MSP compliance obligations, such as Section 111 reporting, Medicare recovery claims, and Medicare set-aside considerations.

In the author’s experience, an often confusing, or overlooked, point involves situations where an individual may be a Medicare beneficiary even though they are below age 65. While the majority of people enrolled in the Medicare program are 65 years old or older, it is reported that there are approximately 7 million Medicare beneficiaries under age 65.^[1]

How is it that a person younger than 65 years old may become entitled to Medicare? The following is a summary of how that may occur:

How a person under age 65 can become a Medicare beneficiary

There are several ways an individual, who is younger than 65 years old, can become Medicare eligible, including:

Social Security Disability;
End Stage Renal Disease;
Amyotrophic Lateral Sclerosis (ALS) (Lou Gehrig’s disease); or
Survivors Benefits.

Each of the above pathways to Medicare entitlement comes with its own intricate rules regarding eligibility, a detailed review of which is beyond this article’s scope. However, the following provides a general overview into each of these potential bases for Medicare entitlement to provide better insight into how a person under age 65 may become a Medicare beneficiary as follows:

Social Security Disability (SSDI)

By far the most common avenue for people under age 65 to become eligible for Medicare is through the receipt of Social Security Disability (SSDI) benefits. For example, per CMS data released in 2023 (which, per the author’s research, is CMS’s most current data), approximately 96% of all Medicare beneficiaries under age 65 became Medicare eligible due to receipt of SSDI benefits.^[2]

In general, SSDI is a program which provides monthly benefits to certain qualified people who are unable to work.^[3]In order to qualify for SSDI, a person needs to have a disability that impacts their ability to work for a year or longer, or is expected to result in their death, and they must have a sufficient work history to qualify for SSDI benefits.^[4] Generally speaking, this means that someone must have worked five of the last ten years prior to their date of disability.^[5]Eligible individuals can apply for SSDI and, if approved, will begin receiving monthly cash benefits after a five month waiting period.^[6]

After twenty-four months of receiving SSDI benefits a disabled individual will become entitled to Medicare.^[7]Medicare benefits can even continue if the person is later able to return work. Specifically, the Social Security Administration (SSA) offers several return-to-work programs and incentives to SSDI beneficiaries which may allow an SSDI beneficiary to continue their Medicare eligibility for some time after they have returned to work.^[8]

While SSDI benefits can result in Medicare entitlement for a person younger than 65 years old it is important to note that this is not the case regarding some other types of Social Security benefits. For example, Supplementary Security Income (SSI) benefits (which are different from SSDI benefits) do not provide entitlement to Medicare.^[9]However, if a person qualifies for both SSDI and SSI concurrently, they would become entitled to Medicare through SSDI, after the applicable waiting period.^[10] Likewise, electing to receive Social Security Retirement benefits early does not entitle a recipient to Medicare before age 65.^[11]

End Stage Renal Disease (ESRD)

There are two medical conditions which may offer an individual expedited entitlement to Medicare. The first is End-Stage Renal Disease (ESRD). According to Medicare, ERSD occurs when someone has “permanent kidney failure that requires a regular course of dialysis or a kidney transplant.”^[12] People with ESRD can become eligible for Medicare if their kidneys no longer work, they need regular dialysis or have had a kidney transplant, and they either have enough work history, are already receiving Social Security or Railroad Retirement benefits, or are the spouse or dependent child of a person who meets the work history requirements.^[13]

Unlike SSDI, the waiting period for Medicare benefits for people with ESRD varies based upon the person’s condition and medical treatment. If the person is on dialysis, Medicare coverage typically starts on the first day of the fourth month of dialysis treatments, though coverage can begin as early as the first month of dialysis treatments if certain conditions are met.^[14]For people getting a kidney transplant, Medicare coverage can begin the month they are admitted to a Medicare-certified hospital for a kidney transplant.^[15]

Amyotrophic Lateral Sclerosis (ALS) (Lou Gehrig’s disease)

The other medical condition that can provide expedited Medicare entitlement is Amyotrophic Lateral Sclerosis (ALS), often referred to as Lou Gehrig’s Disease. For people who are approved for SSDI benefits and have ALS, there is no waiting period for Medicare entitlement if the person’s SSDI Notice of Award is dated on or after July 23, 2020.^[16]This means that both the five month waiting period for receipt of SSDI monthly benefits and the twenty-four month waiting period for Medicare eligibility are waived for SSDI beneficiaries with ALS.^[17]

Survivor Benefits

The SSA also provides Survivor benefits to certain eligible family members of people who worked and paid Social Security taxes prior to their death.^[18]These benefits can be paid to eligible spouses, divorced spouses, children, or dependent parents of deceased individuals.^[19]A full outline of the Survivor benefits program is beyond the scope of this article, however the author notes that the spouse or ex-spouse of a deceased individual may be eligible for Medicare based on the receipt of Survivor benefits if the survivor is over the age of 50 and is found to be disabled.^[20] The disability determination process, as well as applicable waiting periods for cash benefits and Medicare entitlement, are the same for disabled Survivor benefits and SSDI.^[21]

MSP Considerations

Overall, the author hopes the above is helpful in shedding some light regarding how a person younger than 65 years old may become entitled to Medicare. Perhaps the key takeaway from the above is to recognize there are factors other than age that may make someone eligible for Medicare benefits. With that noted, remember that CMS’s Section 111 Query process can be a valuable tool to help determine the claimant’s Medicare status which, in turn, can help insurers start the process of determining potential MSP obligations.

Questions?

Please do not hesitate to contact the author if you have any questions.

[1] Cubanski, J., Freed, M., Ochieng, N., Cottrill, A., Funglesten-Biniek, J. and Neuman, T. (2025, October 5). KFF. What is Medicare? https://www.kff.org/medicare/health-policy-101-medicare/?entry=table-of-contents-what-is-medicare

[2] Id.

[3] https://www.ssa.gov/disability

[4] https://www.ssa.gov/disability/eligibility

[5] The precise work history required to qualify for SSDI benefits depends on a person’s recent work history, lifetime work history, and age. More detail can be found at: https://www.ssa.gov/benefits/disability/qualify.html.

[6] The five-month waiting period typically begins when SSA determines the person became disabled, with the caveat that SSA can generally only pay benefits for up to 12 months before an SSDI application was filed. See https://www.ssa.gov/benefits/disability/qualify.html

[7] https://www.ssa.gov/disability/amount

[8] https://www.ssa.gov/disability/work

[9]https://www.ssa.gov/medicare/sign-up In general, Supplemental Security Income (SSI) is another disability program which is often confused with SSDI. While SSI also pays monthly benefits to disabled individuals and older adults, the key distinction is that SSI does not have the work history requirements of SSDI, but requires beneficiaries to have limited income and few financial resources. https://www.ssa.gov/ssi While many SSI beneficiaries qualify for Medicaid, SSI does not entitle a person to Medicare benefits. https://www.ssa.gov/ssi/text-other-ussi.htm However, as noted above, it is possible to qualify for both SSDI and SSI concurrently, in which case a person’s entitlement to SSDI benefits will entitle them to Medicare after the applicable waiting period. https://www.usa.gov/social-security-disability

[10] https://www.usa.gov/social-security-disability

[11]https://www.ssa.gov/benefits/retirement/matrix.html In general, Social Security Retirement benefits are monthly benefits paid to people who are at least 62 years old and paid Social Security taxes for 10 years or more of their working career. https://www.ssa.gov/retirement As of January 2026, the SSA provided monthly retirement benefits to 56 million people. https://www.ssa.gov/policy/docs/quickfacts/stat_snapshot/ In general, people considering applying for Social Security Retirement benefits must decide when to begin receiving these benefits, as claiming these benefits early provides a lower monthly amount, while delaying enrollment can increase a person’s monthly benefit amount. Social Security Administration (2024), When to Start Receiving Retirement Benefits. Publication Bo. 05-10147. https://www.ssa.gov/pubs/ While many people receiving Social Security Retirement benefits are also enrolled in Medicare, receipt of Social Security Retirement benefits does not change a person’s Medicare eligibility date, which remains age 65 absent early eligibility from one of the above pathways.

[12] https://www.medicare.gov/basics/end-stage-renal-disease

[13] Id.

[14] Id.

[15] Id.

[16] https://secure.ssa.gov/poms.nsf/lnx/0410105075

[17]https://secure.ssa.gov/poms.nsf/lnx/0411036001

[18]https://www.ssa.gov/survivor

[19] Id.

[20] https://secure.ssa.gov/poms.nsf/lnx/0410110001

[21]Id.