You can get on Medicare at age 65. That’s the standard eligibility age, and it hasn’t changed for 2025 or 2026. But 65 isn’t the only way in. People with certain disabilities or medical conditions can qualify much earlier, sometimes at any age.
The Standard: Age 65
Most people become eligible for Medicare when they turn 65. To qualify for premium-free Part A (hospital coverage), you need to be 65 or older and eligible for Social Security or Railroad Retirement Board benefits. You don’t have to be collecting those benefits yet, just eligible for them.
If you’re not eligible for Social Security, you can still enroll in Part A at 65, but you’ll pay a monthly premium for it. In either case, Part B (which covers doctor visits and outpatient care) requires a separate monthly premium. To enroll in Medicare at all, you must be a U.S. citizen or a permanent resident who has lived in the country continuously for at least five years.
Your Enrollment Window at 65
Your Initial Enrollment Period lasts seven months: it starts three months before the month you turn 65 and ends three months after. If you’re already receiving Social Security or Railroad Retirement benefits, you’ll be automatically enrolled in Parts A and B. You’ll get paperwork a few months before your 65th birthday, and you can opt out of Part B if you don’t want it.
If you’re not yet collecting benefits, you need to sign up yourself. Railroad retirees should contact the Railroad Retirement Board directly rather than Social Security, since the RRB handles their Medicare enrollment.
Qualifying Before 65 Through Disability
If you receive Social Security Disability Insurance (SSDI), you become eligible for Medicare after a 24-month waiting period. The clock starts with your first month of disability benefit entitlement, not your diagnosis date or the date you applied. After 24 consecutive months of receiving SSDI, Medicare kicks in automatically.
One useful detail: if you had a previous period of disability, those months may count toward the 24-month requirement. This applies if your new disability begins within 60 months of when your previous benefits ended. For disabled widows, widowers, or adults who qualified through childhood disability benefits, the window extends to 84 months. And if your current condition is the same as or directly related to a prior disabling condition, there’s no time limit at all. Previous months count regardless of the gap.
ALS: No Waiting Period
Amyotrophic lateral sclerosis (Lou Gehrig’s disease) is one of the few conditions that bypasses the 24-month waiting period entirely. If you’re diagnosed with ALS and begin receiving SSDI, your Medicare coverage starts the same month your disability benefits begin. There is no age requirement.
Kidney Failure: Coverage at Any Age
End-stage renal disease (ESRD), meaning permanent kidney failure requiring dialysis or a kidney transplant, qualifies you for Medicare regardless of your age. You do need a work history connection: either you, your spouse, or a parent you depend on must have worked enough under Social Security or as a government employee, or must be receiving or eligible for Social Security or Railroad Retirement benefits.
The timing of when coverage starts depends on your treatment. If you’re on dialysis, Medicare coverage typically begins on the first day of the fourth month of treatment. You can skip that three-month wait if you train for home dialysis at a Medicare-certified facility during those first three months and your doctor expects you to complete the training.
If you’re getting a kidney transplant, coverage can start the month you’re admitted to the hospital for the transplant, as long as the surgery happens that same month or within the next two months. If the transplant gets delayed beyond that, coverage can begin two months before the actual procedure.
There’s also a coordination period to be aware of. If you have employer or union health insurance and you qualify for Medicare only through kidney failure, your employer plan remains the primary payer for the first 30 months. During that time, Medicare acts as a secondary payer, picking up costs your employer plan doesn’t cover.
What Happens If You Delay Past 65
If you’re still working at 65 and have health insurance through an employer with 20 or more employees, you can delay Medicare Part B without penalty. Your employer plan remains primary, and once you stop working or lose that coverage, you’ll get a Special Enrollment Period to sign up.
The key number is 20 employees. If your employer has fewer than 20 workers, the Medicare Secondary Payer rules don’t apply the same way, and delaying could cost you. Without qualifying employer coverage, every full 12-month period you wait past your Initial Enrollment Period adds a 10% penalty to your Part B premium, and you pay that higher amount for as long as you have Part B. Wait two years, and your monthly premium jumps 20% above the standard rate. In 2026, that standard premium is $202.90, so a 20% penalty means paying roughly $40 more every month, permanently.
Part A generally has no penalty if you qualified for premium-free coverage. But if you have to pay for Part A and you delay enrollment, a separate penalty applies: your premium goes up 10%, and you pay the higher amount for twice the number of years you were late.
Quick Reference by Situation
- Turning 65 with Social Security eligibility: Enroll during your 7-month window around your birthday
- Turning 65 while still working: You can delay if your employer has 20+ employees and you have group coverage
- Receiving SSDI: Medicare begins after 24 months of benefits
- Diagnosed with ALS: Medicare starts immediately with SSDI, no waiting period
- Permanent kidney failure: Eligible at any age, with coverage starting as early as the first month of dialysis or the month of transplant admission