You can sign up for Medicare starting three months before the month you turn 65

Medicare enrollment opens during a window, not on a single day. If you turn 65 in June, you can sign up starting in March. The enrollment period lasts seven months total — three months before, the month you turn 65, and three months after. Missing this window can cost you money in late penalties that last for life, so the timing matters.

You do not have to wait until you turn 65 to start the process. Many people sign up two or three months early because the paperwork takes time, and you want coverage to start on the first day of the month you turn 65. If you miss your initial enrollment window, you can still sign up during the general enrollment period (January 1 to March 31 each year), but your coverage will not start until July 1, and you may owe a permanent penalty on your premiums.

Key Takeaways

  • Your initial enrollment window opens three months before you turn 65 and closes three months after, giving you seven months total to sign up without penalty.
  • If you miss your initial window, you can sign up during general enrollment (January 1 to March 31), but coverage starts July 1 and you will owe a late penalty for life.
  • You can sign up online at Medicare.gov, by phone at 1-800-MEDICARE, or in person at your local Social Security office.
  • Some people may have access to for special enrollment periods outside the normal windows if they lose employer coverage or move to a new state.

Your initial enrollment window: the seven-month period around your 65th birthday

The initial enrollment window is the easiest time to sign up because you face no penalty for waiting until the last day. It runs from the first day of the third month before you turn 65 through the last day of the third month after. If your birthday is June 15, your window is March 1 to September 30. You can sign up any day in that range and face no extra cost.

Most people sign up in the month before they turn 65 or the month they turn 65, because that gives the Social Security Administration time to process the paperwork and have your coverage start on the first day of your birthday month. If you sign up in March for a June birthday, your coverage typically starts June 1. If you wait until September, your coverage may not start until October 1, which means you have a gap.

The exact dates depend on your birthday. Social Security publishes the window for each birth month on Medicare.gov. Write down your window as soon as you know you are approaching 65 — do not rely on memory.

What happens if you miss your initial window

If you do not sign up during your initial seven-month window, you can still enroll during the general enrollment period: January 1 to March 31 each year. However, two things change. First, your coverage will not start until July 1 of that year, which means you have been uninsured for months. Second, you will owe a permanent late penalty on your Part B and Part D premiums for as long as you have Medicare.

The late penalty is calculated as a percentage of the standard premium, multiplied by the number of months you were late. For Part B, the penalty is roughly 10 percent of the standard premium for each year you delayed. If you were 12 months late, you owe 10 percent extra forever. If you were 24 months late, you owe 20 percent extra forever. The penalty does not go away when you turn 75 or after a certain number of years — it stays with you.

There is one exception: if you had employer health insurance when you turned 65 and did not sign up for Medicare because of that coverage, you may not owe a penalty when you finally do sign up. This is called a special enrollment period. You must sign up within eight months of losing the employer coverage to avoid the penalty. Keep your employer coverage documents to prove you had insurance when you turned 65.

Special enrollment periods: when you can sign up outside the normal windows

A special enrollment period lets you sign up for Medicare outside your initial window or the general enrollment period without facing a late penalty. The most common reason is losing employer health insurance. If you were covered by your employer's plan when you turned 65 and did not sign up for Medicare, you have eight months after losing that coverage to sign up penalty-free.

Other reasons for a special enrollment period include moving to a new state, losing Medicaid coverage, or having a family member become your representative. If you think you may have access to for a special enrollment period, call 1-800-MEDICARE and explain your situation. Social Security will tell you whether you are may be able to access and what documents you need to prove it.

How to sign up: three ways to enroll

You can sign up online at Medicare.gov, the official government website. Go to the "Sign Up for Medicare" section, answer the questions about your age and citizenship, and follow the steps. You will need your Social Security number and information about any current health insurance. The online process usually takes 15 to 20 minutes. You will get a confirmation number at the end.

You can also call 1-800-MEDICARE (1-800-633-4227) and speak to a representative. They can walk you through the questions and submit your information over the phone. The wait time varies by time of day and season — it is usually shorter in the morning and longer in the afternoon. Have your Social Security number and insurance information ready before you call.

A third option is to visit your local Social Security office in person. You can find the nearest office at ssa.gov. Bring your Social Security card, proof of citizenship (passport, birth certificate, or naturalization papers), and proof of residency (utility bill or lease). An employee will help you fill out the form and submit it on the spot.

What documents you will need to have ready

Before you sign up, gather these documents: your Social Security number, your date of birth, your citizenship status (you must be a U.S. citizen or permanent resident), and proof of residency if you are signing up in person. If you have current health insurance, have your policy number and the name of your insurance company ready. If you are signing up because you lost employer coverage, have the date you lost it and the name of the employer.

If you are signing up for Part D (prescription drug coverage), you will need to choose a plan. Medicare.gov has a tool that shows plans available in your area and what drugs they cover. Look up your current medications before you sign up so you can pick a plan that covers them at a reasonable cost. You do not need to have this information before you start the enrollment process, but having it ready makes the process faster.

When your coverage starts: the first of the month rule

Medicare coverage starts on the first day of a month, not on the day you sign up. If you sign up in March for a June birthday, your coverage starts June 1. If you sign up on June 15, your coverage starts July 1. The Social Security Administration processes applications in batches, so the exact start date depends on when you submit and how busy they are.

For this reason, sign up at least one month before you want coverage to start. If you turn 65 on June 15 and want coverage to start June 1, sign up by May 15. If you sign up on June 20, your coverage will not start until July 1, leaving you uninsured for part of June.

Frequently Asked Questions

Can I sign up for Medicare before I turn 65?

Yes. Your enrollment window opens three months before your 65th birthday. If you turn 65 in September, you can sign up starting in June. Signing up early gives Social Security time to process your process so coverage can start on your birthday month.

What if I am still working at 65?

You can still sign up for Medicare at 65 even if you are working and have employer health insurance. However, if you have employer coverage, you may not owe a penalty if you delay signing up. Ask your employer's benefits department whether you should sign up now or wait. If you do wait, sign up within eight months of leaving the job to avoid a permanent penalty.

Do I have to sign up for all parts of Medicare at the same time?

No. You can sign up for Part A (hospital insurance) and Part B (medical insurance) at one time, and Part D (prescription drug coverage) at another. However, delaying Part D can result in a permanent penalty if you do not have other creditable prescription coverage. Part A has no late penalty.

What if I miss the important date by a few days?

If you miss your initial enrollment window by a few days, you can still sign up during the general enrollment period (January 1 to March 31), but your coverage will not start until July 1 and you will owe a late penalty. There is no grace period — the important date is firm.

Can someone help me sign up if I am not comfortable doing it online?

Yes. You can call 1-800-MEDICARE and have a representative help you over the phone, or visit your local Social Security office and have an employee help you in person. Both are free. You can also ask a family member or trusted friend to help you at home.