When Is Open Enrollment For Medigap? 
Unlike Medicare Advantage Plans , Open Enrollment for Medicare Supplements vary by State . Generally most States have a six month Open Enrollment Period after Turning 65 to enroll in a Medicare Supplement on a Guaranteed Issue basis . After your Open Enrollment Period you will be able to change your Medicare Supplement at any time subject to the companies underwriting requirements , meaning you must qualify health wise . Keep in mind you will also need to pick up a Prescription Drug Plan -LRB- Medicare Part D -RRB- . The Initial Election Period for Medicare Part D is three months before , the month of and three months after you turn 65 . 