When Can I Sign Up For Medicare Part B? 
You will enrolled for Medicare Part A automatically when you turn 65 . If you are receiving Social Securiy you will be enrolled in Part B automatically and Social Security will start deducting your Part B premium from your monthly Social Security Benefit . If you are not receiving Social Security benefits Medicare will notify you 4 to 6 months prior to your Medicare open enrollment period that you are eligible for Medicare the first day of your birth month on your 65th birthday . Your Open Enrollment Period is a 7-month period beginning 3-months before your 65th birthday and 3-months after . You can reply to the Medicare enrollment reminder to enroll you in Medicare or you can decline Part B . If you are not receiving Social Security benefits you will have to pay the first 3-months of your Part B premium by check or money order . You can decline Part B without penalty as long as you are enrolled in an qualified employer health care plan . If you are not enrolled in such a plan you will be penalized 10 % each year when or if you apply for Part B . You can also use the Medicare.gov website to enroll online . 