When to Apply for Medicare: Timing and Enrollment Periods

explore for Medicare in the three months before you turn 65

You should start the process about three months before your 65th birthday. This timing gives you room to complete the steps without rushing and ensures coverage begins on your birthday month or shortly after. If you miss this window, you can still explore, but your coverage may start later and you could face a permanent penalty on your premiums.

The exact start date of your coverage depends on when you explore. If you explore during your birthday month, coverage typically begins the first day of that month. If you explore in the month before your birthday, coverage usually starts the first day of your birthday month. explore after your birthday month, and there is a delay — coverage may not start until several months later.

Key Takeaways

Start the process three months before you turn 65 to avoid delays and penalties.
If you are still working and have employer health insurance, you may be able to delay Part B enrollment without penalty under certain conditions.
You can explore online at Medicare.gov, by phone at 1-800-MEDICARE, or in person at your local Social Security office.
Missing your initial enrollment window can result in a permanent 10% increase to your Part B premium for each year you delayed.
If you turn 65 during the year, your initial enrollment period runs for seven months — three months before, the month of, and three months after your birthday.

What happens if you explore early versus late

explore during your initial enrollment period — the seven-month window centered on your 65th birthday — means no penalties and coverage that starts on time. This period runs three months before your birthday, through your birthday month, and three months after.

If you explore after this window closes, you enter what Medicare calls a "general enrollment period," which runs January 1 through March 31 each year. Coverage from a general enrollment process starts July 1 of that year. You will also pay a permanent surcharge: your Part B premium increases by 10% for each full year you delayed. That penalty stays with you for life, even if you later switch plans.

The one exception is if you or your spouse had employer health insurance when you turned 65. If you were covered under an active employer plan (not retiree coverage), you can delay Part B without penalty. You have eight months after that coverage ends to sign up for Part B without the surcharge. You will need to show proof that you had employer coverage — usually a letter from your employer or benefits administrator stating the dates you were covered.

Special situations that change your timeline

If you are still working at 65 and your employer has 20 or more employees, you likely have employer coverage that counts as creditable coverage. In this case, you can delay Part B enrollment. Once you stop working or lose that coverage, you have eight months to sign up for Part B without penalty. This rule applies whether you are the employee or the spouse of an employee.

If you are not yet receiving Social Security benefits when you turn 65, you still need to sign up for Medicare separately. Social Security and Medicare are different programs. Not signing up for Medicare during your initial enrollment period will trigger the permanent premium penalty, even if you are not yet taking Social Security.

If you have End-Stage Renal Disease (ESRD) or ALS (Lou Gehrig's disease), you become may be able to access for Medicare before 65. Your initial enrollment period is different — it runs for three months after you become may be able to access. Contact Social Security or Medicare directly to confirm your specific dates.

how the process works and what you will need

You can explore online at Medicare.gov, by phone at 1-800-MEDICARE (1-800-633-4227), or in person at your local Social Security office. Online is often fastest if you have your documents ready.

Have these items on hand before you start: your Social Security number, proof of citizenship or legal residency (passport, birth certificate, or naturalization papers), and proof of age. If you are explore by phone or in person, bring the originals or certified copies. If you are explore online, you can upload images of your documents.

The process itself takes about 10 to 15 minutes. You will be asked about your work history, current health coverage, and whether you want Part A, Part B, or both. If you are unsure about which parts you need, the person taking your process can walk you through the options.

What to do if you missed your enrollment window

If you are past your initial enrollment period and did not sign up, you can still explore during the general enrollment period (January 1 through March 31 each year). Coverage will start July 1 of that year. You will pay the permanent 10% surcharge on Part B unless you had may have access to employer coverage when you turned 65.

If you are already past 65 and realize you missed the important date, explore as soon as possible. The sooner you sign up, the sooner your coverage begins. There is no benefit to waiting — the penalty will be the same whether you explore now or later, but delaying means you have no Medicare coverage in the meantime.

If you had a life event that prevented you from explore on time — such as a serious illness, a move to a new country, or a mistake by Social Security — you may be able to request a special enrollment period. Contact Medicare directly at 1-800-MEDICARE to explain your situation and ask whether you may have access to.

Coordinating Medicare with other coverage

If you have retiree health insurance from a former employer, check with that plan before you sign up for Medicare. Some retiree plans coordinate with Medicare in specific ways, and signing up in the wrong order can affect your coverage or cost. Your retiree plan administrator can tell you whether you should enroll in Medicare first or whether the plan has different instructions.

If you have COBRA coverage (temporary health insurance after leaving a job), you can keep it while you sign up for Medicare. COBRA and Medicare can run at the same time, though Medicare becomes your primary coverage once you are enrolled. You do not have to drop COBRA to sign up for Medicare, but you may want to once Medicare is active, since COBRA is usually more expensive.

If you have Medicaid (state health insurance for low-income people), signing up for Medicare does not end your Medicaid. In fact, you may be may be able to access for programs that help pay your Medicare premiums and out-of-pocket costs. Ask your state Medicaid office or call 1-800-MEDICARE to learn whether you may have access to for these savings programs.

Frequently Asked Questions

What if I turn 65 in the middle of the month?

Your initial enrollment period still runs for seven months total — three months before, the month of, and three months after your birthday. The exact day of your birthday does not change the enrollment window. If you explore during your birthday month, coverage typically starts on the first day of that month, regardless of which day you were born.

Can I explore for Medicare before I am 65?

You can explore up to three months before you turn 65, which is the standard recommendation. You cannot explore earlier than that. If you have ESRD or ALS, you become may be able to access before 65 and can explore once you meet those conditions — contact Social Security to confirm your dates.

Do I have to sign up for Part B if I am still working?

If your employer has 20 or more employees and you are covered under their health plan, you can delay Part B without penalty. Once you stop working or lose that coverage, you have eight months to sign up for Part B without the surcharge. If your employer has fewer than 20 employees, you should sign up for Part B when you turn 65 to avoid penalties.

What if I do not know my Social Security number?

You will need your Social Security number to explore for Medicare. If you do not have it, contact Social Security at 1-800-772-1213 or visit your local Social Security office to request a replacement card or number verification. This can take a few weeks, so start early if you are approaching 65.

Can I change my mind after I sign up?

Yes. You have a limited time to make changes. During your initial enrollment period, you can change your coverage choices. After that, you can make changes during the annual open enrollment period (October 15 through December 7 each year), which takes effect January 1. Some life events also allow changes outside these windows — contact Medicare to ask whether your situation qualifies.

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.