If you have been receiving Social Security Disability Income (SSDI) for 24 months, you will automatically get Medicare both Part A and Part B. There is one exception to this rule. If you have amyotrophic lateral sclerosis (ALS), your Medicare will begin as soon as your SSDI begins. Part A is Medicare’s inpatient insurance. It covers hospital visits and skilled nursing facilities. Part B is Medicare’s outpatient insurance. It covers doctor’s visits, lab tests, durable medical equipment and other outpatient services. There is a monthly premium for Part B.

Some people choose to turn down Part B during their Initial Enrollment Period (IEP) because they or their spouse (or other family member) are still working and they have primary insurance from a current employer. If you have insurance from an employer you should talk to your employer to see how your coverage will work with Medicare.

Your Initial Enrollment Period begins three months before your 25th month of receiving SSDI and ends three months after your 25th month of receiving SSDI. If you or your spouse (or other family member) are still working and you receive health insurance from that current employer, the insurance is primary if there are 100 or more employees at the company where you or your spouse (or other family member) work.

If your employer insurance is primary, you can delay enrollment in Part B without penalty. If you are thinking about turning down Part B, you should call the Social Security Administration at 800-772-1213 and ask if you can do that without any penalties. When you call Social Security it is important to write down who you spoke to, when you spoke to them and what they said.

Since you are automatically enrolled in Part B, you will need to actively turn it down if you choose to. To turn down Part B you will need to send back the Medicare card that you got on the mail with the form you received stating that you want to turn down Part B. Keep a copy of the form that you send back to Social Security. You will receive a new Medicare card in the mail that only has Part A on it.

If there are fewer than 100 employees at the company where you or your spouse (or other family member) are currently working, Medicare is your primary coverage. You should not delay enrollment into Part B. If you decline Part B, you will have no primary insurance, which is essentially like having no insurance at all.

In either case, if you have insurance from your or your spouse’s current employer you qualify for a Special Enrollment Period. You will also qualify for a Special Enrollment Period if you receive health insurance from another family member who is not your spouse if there are 100 or more employees at the company where they work. During this Special Enrollment Period, you can enroll in Part B without penalty. This Special Enrollment Period allows you to enroll in Part B at anytime while you or your spouse (or other family member) are still working and for up to eight months after you lose your employer coverage or stop working.

It is important to remember that COBRA and retiree insurance are not considered current employer insurance and you will not have a Special Enrollment Period if you have COBRA or retiree insurance. If you have COBRA and retiree insurance and delay enrollment in Part B you may have to pay a penalty when go to sign up.

When you turn 65 you will have another Initial Enrollment Period to enroll in Part B. This Initial Enrollment Period starts three months before you turn 65 and ends three months after you turn 65. If you are paying a penalty for late enrollment, you will no longer have to pay the penalty once you turn 65.