Medicare makes it difficult to cancel, or withdraw from, Medicare Part B, and part of this intentional difficulty is not having a simple online form for it through the Medicare.gov
Web site. Because Medicare Part B provides important coverage for most people 65 and older, and because there's a penalty if someone cancels Medicare but then later wants to enroll again, Medicare enrolls everyone automatically at age 65 and wants to make sure no one cancels their coverage without fully understanding the consequences.
So, in order to cancel your Medicare Part B coverage, you have to fill out a form (CMS-1763) with the Social Security Administration, which handles initial Medicare enrollment. In order to do so, you must call your local Social Security office and speak on the phone with a Social Security adviser who can help you fill out this form. Or, you can make an appointment to see a Social Security adviser in person, at your local Social Security office. Once you have filled out the form and submitted it to Social Security, they will send you a letter explaining the consequences of withdrawing from Medicare Part B. Your withdrawal will be effective at the end of the month when you file your request form. To learn more about this process, you can visit the Social Security Administration's Web site page Withdrawing from Medicare Part B.