Medicare Part B Enrollment: When to Apply

Micah Pratt
Researcher & Writer
December 10, 2019

Understanding the Medicare Part B enrollment process can be confusing. Depending on your situation, the requirements for enrollment can differ.  Below, we review different ways in which you may want to enroll in Part B coverage.

Medicare Part B enrollment opportunities

Turning 65? 

If you are turning 65, and do not want to draw Social Security benefits yet,  but want to enroll in Medicare, you can enroll on the Social Security Administration's website. You can apply 3 months prior to turning 65, the month you turn 65, or 3 months after turning 65. Your Medicare Part B benefits will be effective the first day of the month in which you turn 65. Unless your birthday is on the first of the month, then your effective date will be the first day of the prior month. If you enroll after turning 65, your benefits will usually begin on the first day of the following month.

How do I enroll if I am already drawing Social Security benefits?
Since you are already drawing social security you will automatically be enrolled in Part A & B starting the 1st day of the month you turn 65, unless your birthday is on the 1st day of the month.  If your birthday is the first day of the month then your Part A & B coverage will start the first day of the prior month of your birthday.

Changing from employer, or spouse coverage

There are two forms that you will need in order to apply for Medicare Part B.  Print these forms, get them filled out, and drop them off at your local Social Security office.  The first for you need is the Part B enrollment form found here:  Medicare Part B enrollment application.  Another important form is for your (or spouse) employer to show that you have had coverage since you were first eligible for Medicare at age 65.  This is to ensure no penalty is added to your monthly Part B premiums.  Here is the form needed for the employer coverage:

What do I need to do if I have Part A, but am losing my group plan coverage?

To sign up for Medicare Part B, you need to fill out application form CMS40B and take or mail it to your local Social Security office. You will also want to send your employer a CMS-L564E form to be filled out and sent in with your CMS40B application. There is an 8-month Special Enrollment Period that begins the month your group coverage ends or when the employment it is based on ends, whichever comes first.

Other questions surrounding Medicare Part B enrollment

What are the premium costs for Medicare Part B? 

The standard monthly Part B premium in 2020 is $144.60 (up from $135.50 in 2019).1 But how much you'll pay depends on your income.  See below how the Part B premium is figured.

If your yearly income in 2018 (for what you pay in 2020) was*
File individual tax return
File joint tax return
File married & separate tax return
You pay (in 2020)
$87,000 or less $174,000 or less $87,000 or less $144.60
above $87,000 up to $109,000 above $174,000 up to $218,000 Not applicable $202.40
above $109,000 up to $136,000 above $272,000 up to $326,000 Not applicable $376.00
above $163,000 up to $500,000 above $326,000 up to $750,000 above $87,000 and up to $413,000 $462.70
above $500,000 above $750,000 above $413,000 $491.60

*Cost based on Data effective 11/12/19.

Your Part D coverage changes as you spend

What if I don't enroll in Medicare Part B when I am first eligible?

A penalty will be assessed to your Medicare Part B premium if you do enroll after your initial 7-month Part B enrollment period and do not have other creditable coverage through an employer or union.  The penalty could be as much as 10% for each full 12-month period you did not have Part B and were eligible.

Additionally, if you do not sign up for Medicare Part B during your Initial Enrollment Period and you do not have a Special Enrollment Period due to loss of group coverage, you will have to wait until the General Enrollment Period to enroll in Part B. This period occurs from January 1st to March 31st, and your coverage benefits will start on July 1st of that year.

Am I eligible for Part B benefits if I have coverage through the Veteran's Administration?

Medicare and the VA do not work together, but an individual can choose to use either for different health care needs. If you have VA benefits and do not enroll for Part B during your initial enrollment period, you may be assessed the Part B premium penalty if you decide to enroll for Part B at a later date.

Get the benefits you deserve when you turn 65 by enrolling in Medicare. To find out more information about enrolling in Medicare Part B, take a look at our Medicare Part B Enrollment Guide.


  1. Medicare, "Part B Costs"

Content on this site has not been reviewed or endorsed by the Centers for Medicare & Medicaid Services, the United States Government, any state Medicare agency, or any private insurance agency (collectively "Medicare System Providers"). is a DBA of Clear Link Technologies, LLC and is not affiliated with any Medicare System Providers.

Micah Pratt
Written by
Micah Pratt
Related Articles
Blue Cross Blue Shield Medicare Advantage Review
Blue Cross Blue Shield (BCBS) offers a large variety of Medicare Advantage (MA) plans in...
Invalid image
Aetna Medicare Advantage Review
As one of the largest healthcare providers in the country, Aetna serves an estimated 37.9...
Invalid image
Amerigroup Medicare Advantage Review
Handfuls of benefits and a variety of SNPs could assist residents of select states. Amerigroup...