How Do I Enroll in Medicare Part B When I Become Eligible?

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How Do I Enroll in Medicare Part B When I Become Eligible?

When you first become eligible to enroll in Medicare Part B, you’ll need to contact the Social Security department through one of the following methods:

  • Go online to
  • Call the Social Security department at 1-800-772-1213 anytime Monday through Friday from 7 a.m. to 7 p.m.
  • Visit your local Social Security office to enroll.
  • Call the Railroad Retirement Board (RRB) at 1-877-772-5772 if you worked for the railroad.

How do you qualify for Medicare Part B?

Before delving too deeply in how to enroll in Medicare Part B, it’s important to first ensure that you qualify for enrollment. Here are the basic qualifications for enrollment in Medicare Part B:

  • You are within three months of your 65th birthday or are older than 65.
  • You are a US resident.
  • You are either a US citizen or a permanent citizen who has been in the US lawfully for at least five continuous years.

If you meet the above qualifications, then you qualify to enroll in Medicare Part B.

When do you enroll in Medicare Part B?

One of the most important things to remember is once you meet all the qualifications and your Initial Enrollment Period (IEP) begins, you have a limited time to enroll. Otherwise, you may be required to pay a late enrollment penalty on top of your usual premium, and you’ll also have to wait to enroll during the next General Enrollment Period (GEP). Your IEP starts three months before your 65th birthday and lasts seven months. The GEP starts January 1 and goes through March 31 of each year. So if you miss your IEP, you may have to wait some time before you have another chance to enroll.

It’s also important to remember that there is an enrollment relationship between Medicare Part A and Part B. You enroll the exact same way for Medicare Part A as you do for Medicare Part B. It will just be up to you to decide if you want to sign up for both Medicare Part A and Medicare Part B or only one of the two. This often depends on your medical needs.

When does enrollment in Medicare Part A and Part B occur automatically?

In some situations, enrollment in Medicare Part A and Part B will happen automatically, and you don’t have to worry about remembering to contact the Social Security Department to enroll. These are the only instances when enrollment in Part B—coupled with Part A—happens automatically:

  • You are already getting benefits from either Social Security or the RRB.
  • You are under 65, have a disability, and have already been receiving benefits for 24 months.
  • You have Amyotrophic Lateral Sclerosis (ALS), also known as Lou Gehrig’s disease.

If you meet one of the above qualifications, you will get your Medicare card either in your 25th month of disability or three months before your 65th birthday.

What happens if you delay enrollment?

If you don’t sign up for Medicare Part B within the seven-month Initial Enrollment Period, then you may have to pay a monthly late enrollment penalty the entire time you’re enrolled in Part B.

It’s important to try and sign up on time because your monthly premium for Part B could be up to 10% higher for every full year you were eligible for Part B but were not enrolled.

Take the time to plan ahead and verify if you will be automatically enrolled or need to enroll yourself. Again, these higher premiums could be in effect for as long as you are enrolled in Medicare.

In most cases, the rules for late enrollment in Medicare Part A and/or Part B are standard, but there are a few exceptions. If you have health coverage through your employer or your spouse’s employer, you can usually delay Medicare Part B enrollment without being subject to late fees.

If you have additional questions about how to enroll in Medicare Part B that are not addressed in these FAQs, please feel free to reach out to one of our insurance agents.

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