There are a few situations where Medicare enrollment may occur automatically:
If You Are Receiving Retirement Benefits
If you’re already collecting Railroad Retirement Board or Social Security retirement benefits when you turn 65, you will automatically be enrolled Medicare Part A (hospital insurance) and Medicare Part B (medical insurance) if you sign up for Medicare Part B at the time you sign up for retirement benefits (see: Medicare.gov).
If you live outside of the 50 United States or D.C. (for example, if you live in Puerto Rico), you will automatically be enrolled in Medicare Part A, but will need to enroll in Medicare Part B manually.
If You Are Receiving Disability Benefits
If you are under 65 and receiving certain disability benefits from Social Security or the Railroad Retirement Board, you will be automatically enrolled in Original Medicare, Part A, and Part B, after 24 months of disability benefits. The exception to this is if you have an end-stage renal disease (ESRD). If you have ESRD and had a kidney transplant or need regular kidney dialysis, you can apply for Medicare. If you have amyotrophic lateral sclerosis (also known as ALS or Lou Gehrig’s disease), you will automatically be enrolled in Original Medicare in the same month that your disability benefits start (see: Medicare.gov).
If You Don’t Want Medicare Part B
If you’re automatically enrolled in Medicare Part B, but do not wish to keep it, you have a few options to drop the coverage. If your Medicare coverage hasn’t started yet and sent a red, white, and blue Medicare card, you can follow the instructions that come with your card and send it back. If you keep the Medicare card, you keep Part B and will need to pay Part B premiums. If you signed up for Medicare through Social Security, you would need to contact them to drop Part B coverage. If your Medicare coverage has started and you want to drop Part B, contact Social Security for instructions on how to submit a signed request. Your coverage will end the first day of the month after Social Security gets your request.
If you have health coverage through current employment (either through your work or your spouse’s employer), you may decide to delay Medicare Part B enrollment. You should speak with your employer’s health benefits administrator to understand how your current coverage works with Medicare and what the consequences would be if you drop Medicare Part B.
Medicare Part B Late-Enrollment Penalty
If you do not sign up for Medicare Part B when you are first eligible, you may need to pay a late enrollment penalty for as long as you have Medicare. Your monthly Part B premium could be 10% higher for every full 12-month period you were eligible for Part B, but didn’t take it (source: Medicare.gov). This higher premium could be in effect for as long as you are enrolled in Medicare. For those who are not automatically enrolled, there are various Medicare enrollment periods during which you can apply for Medicare. Be aware that, with certain exceptions, there are late-enrollment penalties for not signing up for Medicare when you are first eligible.
One exception is if you have health coverage through an employer’s health plan or your spouse’s employer plan, you can delay Medicare Part B enrollment without paying a late-enrollment penalty. This health coverage must be based on current employment, meaning that COBRA or retiree benefits aren’t considered current employer health coverage.
Medicare Initial Enrollment Period
For most people, enrolling in Medicare Part A is automatic. However, there are several instances where you may have to manually enroll in Medicare Part A and/or Part B during your Initial Enrollment Period (IEP), the seven-month period that begins three months before you turn 65, includes the month of your 65th birthday and ends three months later.
Some situations where you would enroll in Medicare during your initial enrollment include:
If you aren’t receiving retirement benefits:
If you are not yet receiving retirement benefits and are close to turning 65, you can sign up for Medicare Part A and/or Part B during your IEP. If you decide to delay your Social Security retirement benefits or Railroad Retirement Benefits (RRB) beyond age 65, there is an option to enroll in just Medicare and apply for retirement benefits at a later time.
If you do not qualify for retirement benefits:
If you are not eligible for retirement benefits from Social Security or the RRB, you will not be automatically enrolled in Original Medicare. However, you can still sign up for Medicare Part A and/or Part B during your IEP. You may not be able to get premium-free Medicare Part A, and the cost of your monthly Part A premium will depend on how long you worked and paid Medicare taxes. You will still have to pay a Medicare Part B premium.
Medicare General Enrollment Period
If you did not enroll during the IEP when you were first eligible, you could enroll during the General Enrollment Period. The general enrollment period for Original Medicare is from January 1 through March 31 of each year. Remember that you may have to pay a late enrollment penalty for Medicare Part A and/or Part B if you did not sign up when you were first eligible.
Medicare Special Enrollment Period
You may choose not to enroll in Medicare Part B when you are first eligible because you are already covered by group medical insurance through an employer or union. If you lose your group insurance, or if you decide you want to switch from your group coverage to Medicare, you can sign up at any time that you are still covered by the group plan or during a Special Enrollment Period(SEP).
Your eight-month special enrollment period begins either the month that your employment ends or when your group health coverage ends, whichever occurs first. If you enroll during a SEP, you generally do not have to pay a late enrollment penalty.
The Special Enrollment Period does not apply if you’re eligible for Medicare because you have ESRD. Please also keep in mind that COBRA and retiree health coverage are not considered current employer coverage and would not qualify you for a special enrollment period.