Medicare is the main federal health insurance program for people age 65 and older in the United States.
When you turn 65, it is important to know how Medicare eligibility works and what steps you must take to enroll on time.
Enrolling properly helps you avoid gaps in coverage and possible penalties.
Medicare Eligibility at Age 65
If you are turning 65 in 2026, you will generally be eligible for Medicare Parts A and B. Part A helps pay for hospital and inpatient services, and Part B covers doctor visits and outpatient services.
Calculate Your 2026 COLA Increase →Most people qualify for Medicare at age 65 if they are either U.S. citizens or lawful permanent residents and have paid Medicare taxes through work.
You may be enrolled automatically if you already receive retirement benefits from the Social Security Administration (SSA) or the Railroad Retirement Board before turning 65. Otherwise, you must actively sign up for Medicare during your enrollment period.
When Can You Sign Up for Medicare at 65?
Your Medicare Initial Enrollment Period (IEP) starts three months before the month you turn 65, includes the month you turn 65, and continues for three months after your birthday month. This gives you a total of seven months to enroll in Medicare Part A and Part B.
For example, if you turn 65 in July 2026, your Initial Enrollment Period begins in April 2026 and ends in October 2026. Enrolling early in the period ensures your coverage starts as soon as possible.
What Happens If You Are Already Getting Social Security Benefits?
If you are already receiving Social Security or Railroad Retirement benefits at least four months before turning 65, you do not need to sign up manually for Medicare.
The Social Security Administration will enroll you automatically in both Medicare Part A and Part B. Your Medicare card will be mailed about three months before your 65th birthday.
This automatic enrollment makes the process easier, but it also means you should check your mail and personal Social Security account to confirm your Medicare coverage details and effective dates.
What If You Are Not Receiving Social Security Benefits?
If you are not already getting Social Security or Railroad Retirement benefits when you turn 65, you must sign up manually for Medicare. You can sign up by:
- Visiting the Social Security website and creating a my Social Security account to enroll online.
- Calling the Social Security Administration at 1‑800‑772‑1213.
- Visiting your local Social Security office.
You should complete this process during your Initial Enrollment Period to ensure coverage starts when you want it.
How Your Medicare Coverage Start Date Is Determined
The date your Medicare coverage starts depends on when you enroll during your Initial Enrollment Period:
- If you sign up before the month you turn 65, your coverage will usually start the month you turn 65.
- If you sign up during the month you turn 65, your coverage starts the next month.
- If you sign up in the three months after your birthday month, your coverage will start later, after the month you sign up.
For Part A, many people receive it premium‑free if they or a spouse paid Medicare taxes while working. Part B usually requires a monthly premium.
What If You Miss Your Initial Enrollment Period?
If you do not sign up during your Initial Enrollment Period, you may have to wait to sign up during the General Enrollment Period (GEP), which runs from January 1 through March 31 each year. Your coverage would start on July 1 of that year.
Missing your Initial Enrollment Period can also mean you might owe a late enrollment penalty for Part B, which can raise your monthly premium permanently.
What If You Are Still Working at 65?
If you are working and have health insurance through your employer when you turn 65, you may choose to delay Part B enrollment without penalty if your employer has 20 or more employees and you remain covered by employer insurance.
You should confirm your situation with your employer and the Social Security Administration.
In this case, you may qualify for a Special Enrollment Period (SEP) that allows you to sign up for Medicare Part B later without penalty after your employer coverage ends.
What If You Also Want Medicare Part D or Part C?
Part D (prescription drugs) and Medicare Advantage plans (Part C) are optional but often used.
You can enroll in those plans during your Initial Enrollment Period or during other specific enrollment windows after that date.
Must You Be a U.S. Citizen?
Yes. In most cases, to be eligible for Medicare at age 65 you must be a U.S. citizen or a lawful permanent resident who has lived in the U.S. continuously for at least five years.
This eligibility rule ensures you qualify for Medicare coverage in 2026 and beyond.
What Documents Are Needed to Enroll?
To enroll manually, you will need:
- Proof of age (birth certificate or passport).
- Proof of U.S. citizenship or lawful residency.
- Social Security number.
The Social Security website explains what documentation is required when signing up.
What Is the Best Way to Enroll?
The fastest and easiest way to enroll in Medicare at 65 is online through Social Security’s secure portal.
Creating a my Social Security account allows you to see eligibility, apply for Medicare, and track your application status.
