Medicare offers health coverage to millions of Americans, but eligibility is not automatic for everyone. Knowing the requirements ahead of time helps you plan effectively and prevent lapses in coverage.
Eligibility Based on Age
Turning 65 is the most common way to become eligible for Medicare. You qualify if you meet one of these conditions:
- You are a U.S. citizen or lawful permanent resident who has resided in the United States for at least five consecutive years
- You or your spouse contributed Medicare payroll taxes for at least 10 years (40 quarters)
Meeting these criteria makes you eligible for premium-free Part A and allows you to enroll in Part B by paying a monthly premium.
What If Your Work History Is Insufficient?
If you or your spouse have fewer than 40 quarters of Medicare-taxed employment, you can still sign up for Part A by paying a monthly premium. In 2026, that premium can be as high as $565 per month, depending on the number of quarters you have accrued.
Eligibility Based on Disability
You may be eligible for Medicare before turning 65 if you:
- Have collected Social Security Disability Insurance (SSDI) benefits for 24 consecutive months
- Have been diagnosed with Amyotrophic Lateral Sclerosis (ALS), also called Lou Gehrig's disease (Medicare coverage starts the same month as your SSDI benefits, with no waiting period)
- Have End-Stage Renal Disease (ESRD) and need dialysis or a kidney transplant
Eligibility for Certain Groups
Spouses and Ex-Spouses
If your own work history does not meet the quarter requirement, you may qualify through your spouse's or ex-spouse's work record. For ex-spouses, the marriage must have lasted at least 10 years. Learn more in our guide to Medicare coverage for non-working spouses.
Federal Employees
Federal workers enrolled in the Federal Employees Health Benefits (FEHB) program should still sign up for Medicare when they become eligible. The two programs can coordinate to lower your out-of-pocket expenses.
Veterans
Veterans eligible for VA healthcare may also enroll in Medicare. Carrying both forms of coverage gives you greater flexibility in selecting healthcare providers and facilities.
How to Verify Your Eligibility
You can confirm whether you qualify for Medicare by:
- Setting up an account at Medicare.gov
- Calling Social Security at 1-800-772-1213
- Visiting your nearest Social Security office in person
Consequences of Delaying Enrollment
If you are eligible but fail to enroll during your Initial Enrollment Period and do not have qualifying employer coverage, you could face:
- Part B late enrollment penalties (a 10% premium surcharge for every 12-month period you were eligible but did not enroll)
- Part D late enrollment penalties (1% of the national base premium for each month you went without creditable drug coverage)
Planning ahead and staying aware of your eligibility timeline helps you avoid unnecessary penalties and maintain uninterrupted coverage.