Medicare Eligibility Requirements: Who Qualifies in 2025

Medicare Eligibility Overview

Medicare eligibility is determined by three primary factors: age, disability status, and specific medical conditions. Most Americans become eligible when they turn 65, but there are pathways to qualify earlier. Understanding which category applies to you is the first step toward getting the coverage you need.

In addition to meeting one of the eligibility pathways below, you must also satisfy citizenship or residency requirements and may need a certain amount of work history (or your spouse's) to receive premium-free Part A coverage.

• Age 65+

  Most common path

• Under 65 with Disability

  After 24-month SSDI wait

• ALS Diagnosis

  Immediate eligibility

• End-Stage Renal Disease

  Kidney failure at any age

Age 65+ Medicare Requirements

The most common way to qualify for Medicare is by turning 65. If you are a U.S. citizen or permanent legal resident who has lived in the country for at least 5 continuous years, you are eligible for Medicare at age 65, regardless of your health status or whether you are still working. For a deeper look at age-based eligibility, see our guide on how old you have to be to get Medicare.

Under 65: Disability-Based Eligibility

You do not have to be 65 to qualify for Medicare. Younger individuals with qualifying disabilities or certain medical conditions can receive Medicare coverage. Here are the main pathways for those under 65 with a disability:

• Age 65 or Older

  The most common path to Medicare. You qualify at age 65 regardless of whether you are still working or retired.

  Requirements:

  • U.S. citizen or permanent legal resident for 5+ continuous years
  • Age 65 or approaching 65
  • You or your spouse paid Medicare taxes for at least 10 years (40 quarters)

  Note: If you are already receiving Social Security benefits, you will be automatically enrolled in Medicare Parts A and B when you turn 65.

  Learn more about age requirements
• Disability (Under 65)

  Younger individuals with qualifying disabilities can receive Medicare after a 24-month waiting period on Social Security Disability Insurance (SSDI).

  Requirements:

  • Receiving SSDI benefits for 24 consecutive months
  • U.S. citizen or permanent legal resident
  • Disability approved by the Social Security Administration

  Note: The 24-month waiting period begins from the date you first receive SSDI benefits, not from when you applied.

  Read the full disability eligibility guide
• ALS (Lou Gehrig's Disease)

  If you have been diagnosed with ALS, you qualify for Medicare immediately with no waiting period required.

  Requirements:

  • Diagnosed with Amyotrophic Lateral Sclerosis (ALS)
  • Eligible for Social Security disability benefits
  • No 24-month waiting period required

  Note: Medicare coverage begins the same month your SSDI benefits start. ALS is the only condition that waives the standard 24-month waiting period.

• End-Stage Renal Disease (ESRD)

  Permanent kidney failure requiring dialysis or a kidney transplant qualifies you for Medicare at any age.

  Requirements:

  • Diagnosed with End-Stage Renal Disease (ESRD)
  • Need regular dialysis or have had a kidney transplant
  • You, your spouse, or your parent has paid Medicare taxes sufficiently

  Note: Coverage typically begins the 4th month of dialysis treatments, though it can begin sooner with a kidney transplant or home dialysis training.

  Learn about Medicare ESRD coverage

ALS and ESRD: Immediate Eligibility

Two medical conditions provide a direct path to Medicare regardless of age and without the standard 24-month disability waiting period:

For more details, read our guide on Medicare coverage for End-Stage Renal Disease.

Citizenship and Residency Requirements

In addition to meeting age or disability requirements, you must also meet citizenship or residency criteria to qualify for Medicare. If you hold a green card, see our dedicated guide on Medicare eligibility for green card holders.

Work History and Part A Premiums

Your work history (or your spouse's) determines whether you receive premium-free Part A. Medicare taxes are paid through payroll deductions (FICA), and the number of "quarters" you have worked determines your premium tier.

• 40+ quarters (10+ years)

  You or your spouse paid Medicare taxes for 10 or more years

  $0/month

• 30 to 39 quarters (7.5 to 9.75 years)

  Reduced premium for those close to the 40-quarter threshold

  $285/month (2025)

• Under 30 quarters

  Full premium required for fewer than 30 quarters of Medicare tax payments

  $518/month (2025)

For a complete breakdown of all Medicare costs, see our 2026 Medicare costs guide.

Medicare Enrollment Windows

Once you qualify for Medicare, you must enroll during a specific window. Missing your enrollment period can result in gaps in coverage and permanent late enrollment penalties. For a complete overview, see our guide to Medicare enrollment periods.

• Initial Enrollment Period (IEP)

  7 months around your 65th birthday

  Starts 3 months before the month you turn 65, includes your birthday month, and ends 3 months after. This is your primary window to enroll without penalties.

  Learn more
• General Enrollment Period (GEP)

  January 1 through March 31 each year

  If you missed your IEP and do not qualify for a Special Enrollment Period, you can sign up during the GEP. Coverage begins July 1. Late penalties may apply.

  Learn more
• Special Enrollment Period (SEP)

  8 months after losing employer coverage

  Available if you delayed Medicare because you had creditable employer coverage. No late penalty applies when you use an SEP.

  Learn more
• Annual Enrollment Period (AEP)

  October 15 through December 7 each year

  For those already enrolled in Medicare who want to switch Medicare Advantage plans or Part D drug plans. Changes take effect January 1.

  Learn more

Special Situations

Several common life situations can affect your Medicare eligibility and enrollment timing. Here is what you need to know:

• Working Past 65

  If you are still working at 65 and have employer coverage through a company with 20+ employees, you may delay Medicare enrollment without penalty. Your employer plan is considered creditable coverage.

  What to Do:

  You have a Special Enrollment Period (SEP) of 8 months after you or your spouse stops working or loses employer coverage.

  Read more

• Veterans with VA Benefits

  VA benefits and Medicare are separate programs. You can have both, and many veterans choose to enroll in Medicare Part A (which is usually free) as a backup.

  What to Do:

  Enrolling in at least Part A is recommended even if you primarily use VA healthcare.

• Federal Employees (FEHB)

  Federal Employee Health Benefits (FEHB) and Medicare can work together. FEHB continues into retirement, and adding Medicare can reduce your out-of-pocket costs.

  What to Do:

  Most federal retirees benefit from enrolling in both Part A and Part B alongside FEHB.

  Read more

• COBRA Coverage

  COBRA is not considered creditable coverage for Medicare purposes. If you are 65+ and on COBRA, you should enroll in Medicare during your Initial Enrollment Period to avoid late penalties.

  What to Do:

  Do not delay Medicare enrollment because of COBRA. You may face permanent late enrollment penalties.

  Read more

• Spouse's Work Record

  If you have not worked enough quarters on your own, you may qualify for premium-free Part A based on your current spouse's, ex-spouse's (if married 10+ years), or deceased spouse's work record.

  What to Do:

  Contact Social Security to verify your eligibility based on a spouse's record.

• Green Card Holders

  Permanent residents (green card holders) qualify for Medicare once they have lived in the United States continuously for at least 5 years and meet age or disability requirements.

  What to Do:

  The 5-year residency clock starts from the date your green card was issued.

  Read more

Late Enrollment Penalties

If you do not sign up for Medicare when you are first eligible and you do not have creditable coverage, you may face permanent penalties added to your monthly premiums:

Frequently Asked Questions

Related Medicare Eligibility Topics

Explore these related guides for more detail on specific eligibility scenarios, enrollment periods, and coverage decisions:

• Medicare Initial Enrollment Period

  The 7-month window to sign up when you first become eligible

• Medicare Special Enrollment Periods

  When and how to use an SEP after losing employer coverage

• Medicare Part B Late Enrollment Penalty

  How the Part B penalty is calculated and how to avoid it

• Medicare Part D Late Enrollment Penalty

  Understanding the Part D penalty and creditable coverage

• Turning 65: Common Medicare Questions

  Everything you need to know as you approach Medicare eligibility

• Medicare Enrollment Checklist

  Step-by-step checklist to prepare before you turn 65

• When to Enroll if Still Working

  Enrollment rules for those with employer coverage past 65

• Medicare and Employer Coverage

  How Medicare coordinates with employer health insurance

• What Is Medicare Creditable Coverage?

  Which coverage counts to avoid late enrollment penalties

• Medigap Open Enrollment Period

  Your best window to enroll in a Medicare Supplement plan

• Can I Delay Medicare?

  When it makes sense to postpone Medicare enrollment

• Medicare for Green Card Holders

  Eligibility rules for permanent residents