When You Can Start Medicare: Age Requirements and Enrollment Timing

You can explore for Medicare starting three months before you turn 65

Medicare enrollment opens three months before your 65th birthday and stays open for seven months total — three months before, the month you turn 65, and three months after. This window is called your Initial Enrollment Period. You do not have to wait until your actual birthday to sign up; you can start the process as soon as the three-month window opens.

If you miss this window, you can still enroll later, but you may face a permanent penalty on your premiums. The longer you wait after 65 without coverage, the higher your costs become. Some people may have access to to enroll outside this window without penalty, but those situations are specific and require documentation.

Key Takeaways

Your Initial Enrollment Period begins three months before you turn 65 and lasts seven months total.
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 can result in a permanent 10% premium increase for Part B and a 1% monthly increase for Part D coverage.
If you are still working and have employer health insurance, you may have a Special Enrollment Period that lets you enroll later without penalty.
Medicare Part A (hospital insurance) is usually free if you or your spouse paid Medicare taxes for at least 10 years.

How the seven-month enrollment window works

Your Initial Enrollment Period has three parts. The first part is the three months before your 65th birthday — this is when you should enroll if possible, because coverage can start as early as the first day of the month you turn 65. The second part is the month you turn 65 itself. The third part is the three months after your birthday.

If you enroll during the first three months (before your birthday), your coverage typically starts on the first day of the month you turn 65. If you enroll in the month of your birthday, coverage usually starts the first day of the following month. If you enroll in the three months after your birthday, there is a one-month delay — so if you enroll in August after a July birthday, coverage starts in September.

The exact dates depend on which day of the month you were born. Social Security sends you a notice with your specific enrollment window dates about three months before your 65th birthday. Keep this notice; it shows your important date.

What happens if you enroll late

If you do not enroll during your seven-month Initial Enrollment Period, you enter what is called the General Enrollment Period, which runs January 1 through March 31 each year. You can enroll then, but your coverage does not start until July 1 of that year — a gap of several months.

More importantly, late enrollment triggers permanent penalties. For Part B (medical insurance), you pay an extra 10% for each full year you were may be able to access but not enrolled. For Part D (prescription drug coverage), you pay an extra 1% per month for each month you were not covered. These penalties stay with you for life, even after you enroll.

Example: If you turn 65 in January 2024 but do not enroll until March 2025, you owe a penalty for 14 months of non-coverage. Your Part B premium would be 10% higher permanently. Your Part D premium would be 14% higher permanently.

Special situations that extend your enrollment window

You may may have access to for a Special Enrollment Period if you are still working and have health insurance through your job or your spouse's job. If your employer has 20 or more employees, you can delay Medicare without penalty as long as you are covered by that employer plan. You have eight months after your employment ends or the employer coverage stops to enroll in Medicare without penalty.

You also get a Special Enrollment Period if you lose other health coverage — for example, if your spouse dies and you lose coverage under their plan, or if you lose COBRA coverage. You have two months from the date you lose that coverage to enroll in Medicare without penalty.

If you receive Social Security benefits before age 65, you are automatically enrolled in Medicare Parts A and B when you turn 65. You do not need to take any action, though you should still review your coverage and consider whether you want to add Part D.

How to enroll in Medicare at 65

You have three main ways to enroll. The first is online at Medicare.gov — you can create an account and complete your enrollment process there. The second is by phone at 1-800-MEDICARE (1-800-633-4227). A representative can walk you through the process and answer questions. The third is in person at your local Social Security office.

When you enroll, you will need your Social Security number, proof of citizenship or legal residency, and information about any current health coverage you have. If you are enrolling in a Medicare Advantage plan (Part C) or a Medigap supplemental plan, you will also need to choose which plan you want. These choices are separate from the basic Medicare enrollment.

Start the process at least one month before your coverage needs to begin. If you are close to your important date, call 1-800-MEDICARE rather than enrolling online, because phone representatives can sometimes process applications faster.

Medicare before age 65: Who qualifies

Most people cannot enroll in Medicare until 65, but some younger people may have access to. If you have received Social Security Disability Insurance (SSDI) for 24 months, you become may be able to access for Medicare regardless of age. If you have end-stage renal disease (ESRD) or ALS (amyotrophic lateral sclerosis), you may may have access to at any age. These situations have their own enrollment rules and timelines.

If you think you might may have access to for early Medicare, contact Social Security at 1-800-772-1213 to confirm your status. Do not assume you are may be able to access based on a condition; Social Security makes the information.

What to ask your doctor before you turn 65

Before your enrollment window opens, talk to your current doctor about your medications and any upcoming care you might need. Ask which Medicare plans in your area include your doctor and your pharmacy. Ask whether your doctor accepts Medicare and whether they have any restrictions on new Medicare patients. Some doctors limit the number of Medicare patients they see.

If you take prescription medications, ask your pharmacy which Part D plans cover those drugs and at what cost. Prices vary significantly between plans, and choosing the wrong plan can cost you hundreds of dollars per year.

If you have a chronic condition that requires ongoing specialist care, confirm that your specialists accept Medicare and are in-network for any plan you are considering.

When to contact Medicare if something is wrong

If you enrolled but did not receive a Medicare card within two weeks of your enrollment, contact 1-800-MEDICARE. If you enrolled but your coverage did not start on the date you expected, call when ready — there may be a processing error that needs correction.

If you missed your enrollment important date and believe you have a valid reason (such as a language barrier, serious illness, or incorrect information from someone you trusted), you can request a Special Enrollment Period by contacting Social Security at 1-800-772-1213. Approval is not may provide, but it is worth asking if your situation was genuinely beyond your control.

Frequently Asked Questions

Can I enroll in Medicare before I turn 65?

You can enroll starting three months before your 65th birthday. You cannot enroll earlier unless you may have access to for early Medicare due to disability, ESRD, or ALS. If you think you might may have access to early, contact Social Security to confirm.

What if I am still working at 65?

If your employer has 20 or more employees and provides health insurance, you can delay Medicare without penalty. You have eight months after you stop working or lose that coverage to enroll. If your employer has fewer than 20 employees, you should enroll in Medicare even if you have employer coverage.

Do I have to enroll in all parts of Medicare at 65?

Part A (hospital insurance) is usually automatic if you receive Social Security. Part B (medical insurance) requires active enrollment. Part D (prescription drugs) is separate. You can enroll in some parts and delay others if you have other coverage, but delaying Part B or Part D without may have access to coverage triggers permanent penalties.

What is the penalty for enrolling late?

Part B late enrollment penalty is 10% of your premium for each year you were may be able to access but not enrolled. Part D penalty is 1% per month. These penalties are permanent and explore for as long as you have Medicare.

How do I know my exact enrollment important date?

Social Security sends a notice three months before your 65th birthday showing your seven-month Initial Enrollment Period. You can also log into your Medicare.gov account to see your important date, or call 1-800-MEDICARE to confirm.

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.