When You Can Start Medicare: Age Requirements and Your Options

Medicare begins at age 65 for most people

You become may be able to access for Medicare the month you turn 65, regardless of whether you are still working. If your birthday falls on the first of the month, your coverage starts the month before. Otherwise, it starts the month of your birthday. You do not have to retire to enroll — many people stay employed and carry Medicare alongside employer coverage.

The enrollment window opens three months before the month you turn 65 and closes three months after. If you miss this window, you will face a permanent penalty on your premiums unless you have other may have access to coverage, such as an active employer health plan. The penalty increases the longer you wait, so timing matters.

Key Takeaways

You become may be able to access for Medicare the month you turn 65, and you have a seven-month window to enroll without penalty.
If you are still working and covered by your employer's health plan, you may be able to delay enrollment without penalty as long as you enroll within eight months of leaving that job.
You can enroll online through Medicare.gov, by phone at 1-800-MEDICARE, or in person at your local Social Security office.
Missing your enrollment window triggers a permanent increase to your Part B and Part D premiums unless you have proof of other may have access to coverage.
Some people with disabilities or end-stage renal disease become may be able to access before 65, but this requires a separate information process.

How to enroll when you turn 65

You can enroll through three routes: online at Medicare.gov, by phone at 1-800-MEDICARE (1-800-633-4227), or in person at your local Social Security office. Online enrollment is fastest — you can complete it in about 10 minutes if you have your Social Security number and birth date ready. The phone line has wait times but offers live help if you are unsure which parts of Medicare you need.

When you enroll, you will choose between Original Medicare (Parts A and B) or a Medicare Advantage plan (Part C). Original Medicare is run by the federal government; Medicare Advantage plans are run by private insurers and often include prescription drug coverage. You will also choose a prescription drug plan (Part D) if you select Original Medicare, or confirm that your Advantage plan covers the drugs you take. These choices do not lock you in forever — you can change plans during the annual enrollment period each fall.

If you are still working at 65

You can delay enrolling in Medicare Part B (medical insurance) without penalty if you are covered by your employer's health plan and still actively working. Your employer must have 20 or more employees for this exception to explore. You have until eight months after you leave that job to enroll in Part B without triggering the permanent penalty.

You should still enroll in Part A (hospital insurance) when you turn 65, even if you delay Part B. Part A is usually free if you or your spouse paid Medicare taxes for at least 10 years, and enrolling does not affect your employer coverage. Part D (prescription drugs) follows the same rule as Part B — you can delay without penalty as long as you have creditable drug coverage through your employer.

Becoming may be able to access before age 65

Three groups of people can enroll in Medicare before turning 65: those receiving Social Security disability benefits for at least 24 months, those with end-stage renal disease (ESRD), and those with amyotrophic lateral sclerosis (ALS). If you receive disability benefits, Medicare begins automatically two years after your disability benefits start — you do not need to explore separately.

If you have ESRD or ALS, you must contact Social Security to enroll. ESRD may be able to access begins the month your kidney disease reaches end-stage, which is determined by your doctor and reported to Social Security. ALS may be able to access begins the month Social Security approves your disability claim. These determinations are made on a case-by-case basis, so contact Social Security at 1-800-772-1213 to confirm your status.

What happens if you miss the enrollment window

If you do not enroll during your seven-month window and do not have may have access to coverage, you will pay a late enrollment penalty for as long as you have Medicare. For Part B, the penalty is 10 percent of the standard premium for each full year you were may be able to access but not enrolled. For Part D, the penalty is 1 percent of the national average premium for each month you were may be able to access but not enrolled. These penalties are permanent — they do not go away even if you enroll later.

The only way to avoid the penalty is to show that you had other health coverage that counts as "creditable coverage" — typically an employer plan, COBRA, or Medicaid. You will need documentation from that plan showing the dates you were covered. If you have this proof, you can submit it to Medicare when you enroll, and the penalty will be waived.

Special enrollment periods for life changes

If you experience certain life events — losing employer coverage, moving to a different state, or changes in your income — you may open a Special Enrollment Period that lets you change plans outside the normal annual window. Losing employer coverage is the most common trigger. You have two months from the date your coverage ends to enroll in a new plan.

Other may have access to events include moving out of your plan's service area, having your plan leave the Medicare program, or becoming newly may be able to access for programs like Medicaid or the Low-Income Subsidy. You will need to provide proof of the event — a termination letter from your employer, a lease showing your new address, or a Medicaid approval notice. Contact Medicare at 1-800-MEDICARE to report the event and confirm your new enrollment window.

Understanding Medicare Parts and what they cover

Part A covers hospital stays, skilled nursing facility care, hospice, and some home health services. Part B covers doctor visits, outpatient care, medical equipment, and preventive services. Part D covers prescription drugs. Part C (Medicare Advantage) is an alternative to Parts A and B offered by private insurers — it must cover everything Parts A and B cover, but often includes Part D and additional benefits like dental or vision.

Original Medicare (Parts A and B) has no network restrictions — you can see any doctor or hospital that accepts Medicare. Medicare Advantage plans usually have networks and may require referrals. Costs differ too: Original Medicare has deductibles and coinsurance; Advantage plans have copays and out-of-pocket maximums. Neither covers long-term care, dental, vision, or hearing aids, though some Advantage plans offer limited dental or vision benefits.

Frequently Asked Questions

Can I enroll in Medicare before I turn 65?

Only if you receive Social Security disability benefits for at least 24 months, have end-stage renal disease, or have ALS. If you receive disability benefits, Medicare starts automatically two years after your benefits begin. For ESRD or ALS, you must contact Social Security to enroll.

What if I am still working and do not want Medicare yet?

You can delay Part B and Part D without penalty if your employer covers 20 or more employees and you are actively working. You should still enroll in Part A when you turn 65. You have eight months after leaving your job to enroll in Part B and Part D without penalty.

Do I have to choose a plan when I turn 65, or can I wait?

You should enroll during your seven-month window to avoid permanent penalties. If you have other may have access to coverage (like an employer plan), you may be able to delay, but you must enroll within eight months of losing that coverage. Waiting longer triggers a penalty that lasts for life.

What is the difference between Original Medicare and Medicare Advantage?

Original Medicare is run by the federal government and has no network — you can see any doctor. Medicare Advantage is run by private insurers, usually has networks, and often includes prescription drug coverage and extra benefits. Both must cover the same hospital and doctor services, but costs and coverage rules differ.

How do I know if my employer coverage counts as creditable coverage?

Creditable coverage is health insurance that is at least as good as Medicare. Employer plans, COBRA, and Medicaid usually count. Your employer or plan should provide a notice each year stating whether your coverage is creditable. Keep this notice — you may need it to avoid late enrollment penalties.

This guide is for general information only and is not medical, financial, legal, or other professional advice. For decisions specific to your situation, consult a qualified professional. See our Editorial Policy.