Medicare Under 65: 24-Month Wait & ALS/ESRD Exceptions (2026)

If you or someone you love is under 65 and facing a serious illness or disability, Medicare may be available to you long before retirement age. There are three main paths in: a two-year wait after Social Security disability benefits begin, an immediate path for people with ALS, and a separate route for permanent kidney failure. This guide walks through each one, when coverage actually starts, and a few decisions about supplemental coverage that can matter a great deal for younger beneficiaries.

You don't have to figure this out at the worst possible time

A disability diagnosis rarely arrives at a convenient moment. You may be sorting out work, income, and a new medical reality all at once, and now there's a benefits system to decode on top of it. So here's the short version first.

Most people picture Medicare before 65 as something tied only to age. It isn't. Federal law opens three doors for younger people, and which door you go through changes when your coverage starts and what you have to do to get it.

Path #1: Getting Medicare through SSDI

This is the most common way people under 65 reach Medicare, and the timing trips up almost everyone, so it's worth being precise.

When the Social Security Administration approves you for SSDI, your cash benefits don't start the day you're approved. There's a five-month waiting period first, built into the disability program itself. Only after that does your SSDI entitlement actually begin.1

Then the Medicare clock starts. You have to receive SSDI cash benefits for 24 months, and your Medicare coverage begins in the 25th month. The Centers for Medicare and Medicaid Services confirms this two-year rule. The good news in the middle of a hard process: you don't have to apply. CMS states that disabled individuals are automatically enrolled in Medicare Part A and Part B once they have received disability benefits from Social Security for 24 months.1 One group reaches Medicare without that 24-month clock at all: CMS names a separate route for disabled federal, state, and local government employees who are not eligible for monthly Social Security or Railroad Retirement benefits, who may get deemed entitlement to disability benefits and automatic Part A entitlement after being disabled for 29 months.1

One thing about that clock decides whether a whole group of readers even applies, so don't skip it: it is not limited to SSDI on your own work record. Federal law counts 24 calendar months of entitlement to disability insurance benefits, to child's insurance benefits by reason of a disability, or to a disabled widow's or widower's benefits, and it reaches someone who has been a disabled qualified railroad retirement beneficiary for at least 24 months. So an adult disabled child drawing childhood disability benefits on a parent's record, and a disabled widow or widower drawing on a late spouse's record, reach Medicare on the same clock as a worker with their own SSDI. If you have never worked enough to earn SSDI yourself, that does not close the door.2

It's frustrating math, we know. Stacked together, the five-month SSDI waiting period and the 24-month Medicare wait mean a long stretch between disability onset and Medicare coverage. During that gap, many people rely on an employer plan, a spouse's plan, COBRA, a Marketplace plan, or Medicaid. If money for care is tight while you wait, that's exactly the kind of thing worth raising with a benefits counselor sooner rather than later.

Path #2: ALS skips the wait entirely

If the diagnosis is amyotrophic lateral sclerosis (ALS, or Lou Gehrig's disease), the rules are different, and deliberately so. Congress recognized that a two-year wait makes no sense for a fast-moving disease.

There is no 24-month waiting period for ALS. Medicare begins the first month you become entitled to SSDI cash benefits, per Medicare.gov's guidance on getting Medicare before 65. And for ALS claims approved on or after July 23, 2020, the five-month SSDI waiting period described above is gone too, so neither wait stands between the approval and coverage. As with the standard disability path, enrollment is automatic once your SSDI benefits start, so you aren't left chasing paperwork while managing the illness.1

Path #3: End-stage renal disease (ESRD)

The third door is for people with end-stage renal disease, permanent kidney failure that requires regular dialysis or a kidney transplant. ESRD qualifies you for Medicare at any age, with no income test, but not by diagnosis alone. Medicare requires all three of these: your kidneys no longer work, you need regular dialysis or have had a kidney transplant, and one of the following applies to you. Either you have worked the required amount of time under Social Security, the Railroad Retirement Board, or as a government employee; or you already get or are eligible for Social Security or Railroad Retirement benefits; or you are the spouse or dependent child of someone who meets either of those. A person with kidney failure and no work record behind them, their own or a family member's, does not automatically qualify. It also works differently from the first two paths in one important way: enrollment is your choice, not automatic. You decide whether and when to sign up.3

ESRD also has its own start-date rules, and they differ by treatment. On the dialysis route, if your Medicare eligibility is based only on ESRD, coverage usually starts on the first day of the fourth month of dialysis, and that waiting period runs whether or not you have signed up, so holding off on your application does not hold off the clock. It can begin as early as the first month of a regular course of dialysis only if all three of Medicare's conditions are met: you take part in a home dialysis training program at a Medicare-certified training facility during those first three months, your doctor expects you to finish the training and be able to do your own dialysis at home, and you keep up a regular course of dialysis throughout the waiting period that would otherwise apply. A kidney transplant is on a different footing: Part A coverage begins the month of the transplant, or two months earlier if you were hospitalized in those months in preparation for it, so the four-month dialysis wait is not the rule that governs you. Because the timing, the 30-month employer-plan coordination period, and the transplant rules are genuinely involved, we cover them in depth in our dedicated guide, linked below.3

Which disabilities qualify for Medicare under 65?

There is no separate Medicare list of qualifying conditions. For the disability path, you reach Medicare by first qualifying for a Social Security disability benefit, then serving the 24-month qualifying period. Most people get there through Social Security Disability Insurance (SSDI) on their own work record, but childhood disability benefits on a parent's record and disabled widow's or widower's benefits on a late spouse's record start the same 24-month clock.2 So which disabilities qualify you for Medicare is really a question of which conditions Social Security approves: that determination is made by Social Security, not Medicare, and it isn't a fixed list of diagnoses.1

Two diagnoses are handled differently and skip or shorten the wait:

• ALS (Lou Gehrig's disease) skips the 24-month Medicare wait entirely, so coverage begins the first month your SSDI benefits start.1
• End-stage renal disease (ESRD) qualifies you at any age, on its own separate track, as long as the work-history test is met.3

If Social Security has approved you for a disability benefit, you're on the path to Medicare regardless of your specific diagnosis. The timeline, not the condition, is what changes.

Your Medicare under 65 coverage choices are the same, with one asterisk

Getting Medicare through disability doesn't put you in a lesser version of the program. You have the same options as someone who qualified at 65.

That means you can:

• Stay with Original Medicare (Parts A and B) and add a standalone Part D drug plan.
• Choose a Medicare Advantage plan (Part C) that bundles your coverage, usually including drugs.
• Ask your state insurance department whether a Medigap (Medicare Supplement) policy is available to you before 65, since federal law does not require companies to sell one to people under 65 and access varies by state.1 Where it is available, Medigap covers the deductibles and coinsurance Original Medicare leaves to you.

The asterisk is on that last one, and it's important.

Medigap is where being under 65 gets complicated

The federal Medigap protections that guarantee you a policy regardless of your health are written around age 65. The six-month Medigap Open Enrollment Period, the window when insurers must sell you any plan they offer, can't use medical underwriting to accept or reject your application, and can't charge you more because you have health problems, is triggered by being both 65 and enrolled in Part B.5

So what happens if you're 52 and on Medicare through disability? It depends entirely on where you live. Some states allow anyone with Medicare under 65 to buy a Medigap policy. Where a state has not written that protection, Medicare's own warning is that if you have ESRD or a disability, you may not be able to buy the Medigap policy you want, or any Medigap policy, until you turn 65. This is one of the few places in Medicare where your state of residence directly changes what's available to you, so check your own state's rules before assuming a Medigap policy is on the table.1

If Medigap isn't realistically available to you under 65, a Medicare Advantage plan is often the practical alternative, because it puts a ceiling on your year. CMS caps what a plan can charge you out of pocket for in-network Part A and Part B services at $9,250 in 2026, and plans may set their cap lower. Original Medicare has no yearly out-of-pocket limit of its own unless you carry supplemental coverage, meaning Medigap, Medicaid, or employer, retiree, or union coverage. If you have none of those, and many people under 65 on Medicare have none, your exposure under Original Medicare alone really is uncapped. Two limits on the plan cap are worth knowing before you lean on it: it counts Part A and Part B cost sharing only, not what you spend on Part D drugs, and a plan that covers out-of-network care sets a second, higher limit for in-network and out-of-network costs combined.6 It's worth comparing both honestly.

Turning 65 opens a fresh six-month window

This is the part to circle on your calendar. CMS is explicit about it: someone who came onto Medicare before 65 through disability or ESRD is reclassified as an aged beneficiary on attaining age 65, and because they are already entitled to Part B, their Medigap Open Enrollment Period begins on the date they attain age 65. Years already spent on Medicare do not use it up.4

Two timing details decide whether you actually get the window you think you have. First, CMS says the period never begins on your actual birthday: you are treated as attaining age 65 on the first day of the month your 65th birthday falls in, and on the first day of the preceding month if your birthday is the first of a month. Second, you can apply before the window opens. The statute covers an application submitted prior to or during the six months, and CMS says that if you apply early enough you can ask to have the policy start on the first day of your Part B entitlement as an aged beneficiary.4

That means even if you were denied a Medigap policy, or priced out of one, while under 65, those full protections apply to you at 65. One limit is worth knowing before you count on it: the Open Enrollment Period is not the same as a guaranteed issue right, so an insurer can still refuse to cover your out-of-pocket costs for a pre-existing condition for up to six months, unless you had at least six months of continuous creditable coverage beforehand.5 For many people who've spent years on Medicare with a disability, this is the single best opportunity to lock in supplemental coverage they couldn't get before. Don't let it pass unnoticed.

There is also a quiet advantage here that most people aging in at 65 don't have. Plans C and F, the two standardized Medigap plans that cover the annual Part B deductible, are closed to people new to Medicare on or after January 1, 2020. But that test has two halves, and someone who was already entitled to Part A before that date because of a disability or ESRD falls outside the closure. If your Part A started before 2020, ask whether Plan C or Plan F is still on the table for you.5

What Medicare under 65 costs in 2026

Medicare's costs are the same whether you qualified by age or by disability. The figures below are the 2026 amounts for Original Medicare. Part A is premium-free for about 99% of Medicare beneficiaries, on the strength of at least 40 quarters (about 10 years) of Medicare-covered work.6

If you're short of 40 quarters, don't assume a Part A premium is coming. Forty quarters is one sufficient route to insured status, not the definition of it, and federal law does not count a year against you if any part of it fell inside a period of disability, which is precisely the situation of someone whose working years were cut short by illness. A current or former spouse's record can also carry you. Have Social Security test your own record before you conclude you'll be billed.2

If these costs feel out of reach on a disability income, you're not stuck. Medicare Savings Programs run by state Medicaid agencies can pay your Part B premium, and the Part D Low-Income Subsidy (Extra Help) can cut your drug costs. Many people on SSDI qualify, and it's worth asking.

Learn More

Find personalized help navigating Medicare eligibility under 65 at brevy.com.

The information on Brevy.com is for educational purposes only and is not a substitute for professional legal, financial, or medical advice. Rules vary by state and program and change frequently. Always verify with the relevant agency or a qualified professional. Brevy is not a law firm, financial advisor, or healthcare provider.