Age 65

At 65, you become eligible for Medicare. You can sign up during a seven-month period that starts three months before the month you turn 65. Make sure you enroll on time. Otherwise, Part B premiums may go up 10% for each full 12-month period you were eligible for benefits but failed to enroll. If you didn’t sign up because your employer or your spouse’s provided a health plan at work, you need to enroll Medicare within eight months of leaving the job or health plan. If not, you will have to pay certain penalties.