This premium is either deducted from your monthly Social Security benefit check, if you are collecting Social Security, or paid by you directly, if you are Medicare eligible (age 65) and not collecting Social Security. Many of us are still working and have insurance under another plan and elect not to sign up for the Medicare Part B as required at age 65 because we do not want to pay the monthly Part B cost which can carry a surcharge as high as $294.00 depending on your or your family's income. However if you do not want to be penalized certain rules have to be followed: First, the company for which you work has to have at least 20 employees, second you are required to submit a form (CMS-1763) that must be completed either in person or on the phone with a Social Security representative. You have to be interviewed by Social Security as they want to ensure that your company's insurance coverage meets Medicare's requirements and you are aware of the penalty for unauthorized late enrollment. For example, if you are an employee of your spouses's company and he/she has more than 20 employees and you have filled out the above form and been interviewed by Social Security you can waive the Part B premium but if his/her company downsizes and only has 19 employees you must sign up for Part B and pay the premium but you do have eight months from the time the company status changed. You can sign up or disenroll for Medicare Part B multiple times as long as you follow the rules and meet the requirements.