Medicare starts at 65, but you must enroll during your signup window or face penalties

You become may be able to access for Medicare the month you turn 65. You do not automatically receive it — you have to sign up. If you wait past your enrollment window, you will pay a permanent penalty on your premiums for as long as you have Medicare, even if you sign up years later.

The enrollment window is seven months long: three months before the month you turn 65, the month you turn 65, and three months after. For example, if you turn 65 in June, your window runs from March through September. You can enroll online at Medicare.gov, by phone at 1-800-MEDICARE, or in person at your local Social Security office.

Some people do not have to wait until 65. If you have been receiving Social Security disability benefits for 24 months, or if you have end-stage renal disease or ALS, you can enroll earlier. If you are still working and have health insurance through your employer, you may be able to delay enrollment without penalty — but only if your employer has 20 or more employees.

Key Takeaways

  • Your seven-month enrollment window opens three months before you turn 65 and closes three months after.
  • If you miss your window and do not have a valid reason, you will pay a 10 percent penalty on Part B premiums and a 1 percent penalty on Part D premiums for life.
  • You can enroll online at Medicare.gov, by phone, or at your local Social Security office during your window.
  • If you are still working with employer coverage, you may delay enrollment without penalty, but you must tell Medicare when you do enroll.

What counts as a valid reason to enroll late

Medicare recognizes certain situations where you can enroll after your window closes without paying the lifetime penalty. These are called Special Enrollment Periods. The most common one is losing employer health coverage — if your employer coverage ends, you have eight months to enroll in Medicare without penalty.

Other reasons include losing coverage through a family member's job, moving out of your plan's service area, or having your plan terminated. If you were not told about your enrollment window and Medicare determines you had good cause not to know, you may also avoid the penalty. You will need to provide documentation — a termination letter from your employer, proof of the coverage you had, or a written explanation of why you did not enroll.

Contact Medicare at 1-800-MEDICARE to ask whether your situation qualifies for a Special Enrollment Period. They can tell you whether you still have time to enroll without penalty and what documents to gather.

How the late enrollment penalty works

The penalty is permanent and calculated as a percentage of the standard premium. For Part B (doctor and outpatient care), the penalty is 10 percent of the standard premium for each full year you were may be able to access but not enrolled. If you were may be able to access for three years and did not enroll, your penalty would be 30 percent of the current Part B premium, added to your monthly bill for life.

For Part D (prescription drug coverage), 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 do not go away if you later switch plans or if the standard premium changes. They follow you as long as you have Medicare.

The only exception is if you have a valid reason for late enrollment. If Medicare approves your Special Enrollment Period, you can enroll without any penalty at all.

Enrolling before you turn 65

You can start the enrollment process up to three months before your birthday. Many people do this to avoid the rush and to make sure their coverage starts on time. If you enroll in the three months before your birthday, your coverage will begin on the first day of the month you turn 65.

If you enroll during the month you turn 65, your coverage starts the first day of that month. If you enroll in the three months after your birthday, your coverage will start the first day of the following month. For example, if you turn 65 on June 15 and enroll on July 20, your Medicare coverage will not start until August 1.

Enrolling early gives you time to choose your plans carefully and to ask questions if something is unclear. It also means your coverage will not have a gap if you currently have insurance through an employer or a spouse's job.

What to do if you think you missed your window

Do not assume you have to pay the penalty. Contact Medicare at 1-800-MEDICARE or visit Medicare.gov to find out whether your situation qualifies for a Special Enrollment Period. Bring any documents that show why you did not enroll on time — a letter from your employer, proof of other coverage, or a notice that your plan was terminated.

If you do have to pay a penalty, it will be added to your Part B premium each month. You cannot pay it all at once or remove it later. However, if you can show that you had good cause for the late enrollment, Medicare can remove the penalty retroactively. This is rare, but it is worth asking about if your situation was genuinely beyond your control.

If you are already past 65 and have not enrolled, enroll as soon as you can. The sooner you enroll, the sooner your coverage begins and the smaller your total penalty will be.

How to choose your coverage type when you enroll

When you enroll, you will choose between Original Medicare (Part A and Part B) and Medicare Advantage (Part C). Original Medicare is run by the federal government and covers hospital care, doctor visits, and outpatient services. Medicare Advantage is run by private insurance companies and usually includes prescription drug coverage and extra benefits like dental or vision, but it has networks and may require referrals.

You will also choose whether to add Part D (prescription drug coverage). If you have Original Medicare and do not enroll in Part D when you first become may be able to access, you will pay a penalty if you add it later — unless you have other creditable drug coverage, such as through a current or former employer.

Take time to compare plans before you enroll. Medicare.gov has a plan comparison tool that shows you the costs, coverage, and pharmacies for each plan in your area. You can also call 1-800-MEDICARE to speak with someone who can walk you through your options.

Frequently Asked Questions

What if I turn 65 while still working?

You can delay enrolling in Part B without penalty if your employer has 20 or more employees and you are covered by their health plan. You must enroll in Part A (hospital insurance) when you turn 65, even if you are still working. When you leave your job or lose your employer coverage, you have eight months to enroll in Part B without penalty.

Can I change my mind after I enroll?

Yes. You have a seven-month disenrollment period that runs from November 15 to December 31 each year. During this time, you can switch between Original Medicare and Medicare Advantage, or change your Part D plan. Changes take effect January 1 of the following year.

Do I have to enroll in Part A?

If you are receiving Social Security benefits when you turn 65, you are automatically enrolled in Part A and Part B. If you are not receiving Social Security, you must enroll in Part A yourself during your enrollment window. Part A is usually free if you or your spouse paid Medicare taxes for at least 10 years.

What happens if I miss my window and have no Special Enrollment Period?

You can still enroll in Medicare, but you will pay a permanent penalty on your premiums. The penalty is 10 percent of the Part B premium for each year you were may be able to access but not enrolled, and 1 percent of the Part D premium for each month you were may be able to access but not enrolled. These penalties stay with you for life.

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

Creditable coverage means it is at least as good as Medicare coverage. Your employer should tell you in writing whether your coverage is creditable. If you are unsure, ask your employer's benefits department or call 1-800-MEDICARE. If your coverage is creditable, you can delay enrolling in Part D without penalty.