Late Enrollment Penalty
When you turn 65, you're eligible to enroll in Medicare Part B. If you do not enroll in Part B when you're first eligible, you may be subject to the federal late enrollment penalty. The late enrollment penalty is added to your monthly Part B premium for as long as you have Part B. You may also be subject to the late enrollment penalty if you voluntarily terminate your enrollment from Part B and enroll in Part B at a later date.