Medicare Enrollment: How and When to Enroll in Medicare

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You have several options when the time comes for you to enroll in Medicare. For some people, Medicare enrollment is automatic, while for others, it may depend on when and how they become eligible.

How to enroll in Medicare

You can enroll in Medicare Part A and/or Medicare Part B in the following ways:

  • Online at www.SocialSecurity.gov.
  • By calling Social Security at 1-800-772-1213 (TTY users 1-800-0778), Monday through Friday, from 7AM to 7PM.
  • In-person at your local Social Security office.

If you worked at a railroad, enroll in Medicare by contacting the Railroad Retirement Board (RRB) at 1-877-772-5772 (TTY users 1-312-751-4701). You can call Monday through Friday, 9AM to 3:30PM, to speak to an RRB representative.

When to enroll in Medicare

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.

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 manually enroll in Medicare Part B.

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 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.

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 you were sent a red, white, and blue Medicare card, you can follow the instructions that come with your card and send the card 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, then you will 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 so that you 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 that you were eligible for Part B, but didn't take it. 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 health plan or through 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 into 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 can enroll during the General Enrollment Period. The general enrollment period for Original Medicare is from January 1 through March 31 of each year. Keep in mind 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 an 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.

Medicare Advantage plan enrollment

Medicare Advantage, also known as Medicare Part C, is another way to receive Original Medicare benefits and is offered through private insurance companies. At minimum, all Medicare Advantage plans must offer the same Medicare Part A and Part B benefits as Original Medicare. Some Medicare Advantage plans also include additional benefits, such as prescription drug coverage. You must have Original Medicare, Part A and B, to enroll in a Medicare Advantage plan through a private insurer.

You can enroll in a Medicare Advantage plan during two enrollment periods, the Initial Coverage Election Period and Annual Election Period.

Medicare Advantage plan Initial Coverage Election Period:
Most beneficiaries are first eligible to enroll in a Medicare Advantage plan during the Initial Coverage Election Period. Unless you delay Medicare Part B enrollment, this enrollment period takes place at the same time as your Initial Enrollment Period (IEP), starting three months before you have both Medicare Part A and Medicare Part B and ending on whichever of the following dates falls later:

  • The last day of the month before you have both Medicare Part A and Part B, or
  • The last day of your Medicare Part B Initial Enrollment Period.

If you're under 65 and eligible for Medicare due to disability, your IEP will vary depending on when your disability benefits started.

Medicare Advantage plan Annual Election Period:
You can also add, drop, or change your Medicare Advantage plan during the Annual Election Period, which occurs from October 15 to December 7 of every year. During this period, you may:

  • Switch from Original Medicare to a Medicare Advantage plan, and vice versa.
  • Switch from one Medicare Advantage plan to a different one.
  • Switch from a Medicare Advantage plan without prescription drug coverage to a Medicare Advantage plan that covers prescription drugs, and vice versa.

Medicare Advantage Disenrollment Period:
You'll have the opportunity to disenroll from your Medicare Advantage plan and return to Original Medicare during the Medicare Advantage Disenrollment Period, which runs from January 1 to February 14. You cannot use this period to switch Medicare Advantage plans or make other changes. However, if you decide to drop your Medicare Advantage plan, you can also use this period to join a stand-alone Medicare prescription drug plan, since Original Medicare doesn't include prescription drug coverage.

Outside of the Annual Election Period and the Medicare Advantage Disenrollment Period, you cannot make changes to your Medicare Advantage plan unless you qualify for a Special Election Period.

Medicare prescription drug coverage

Medicare prescription drug coverage is optional and does not occur automatically. You can receive coverage for prescription drugs by either signing up for a stand-alone Medicare prescription drug plan or a Medicare Advantage plan that includes drug coverage, also known as a Medicare Advantage Prescription Drug plan. Medicare prescription drug plans and Medicare Advantage plans are available through private insurers. Please note that you cannot have both a stand-alone Medicare prescription drug plan and a Medicare Advantage plan that includes drug coverage.

Initial Enrollment Period for Medicare Part D:
You can enroll in a stand-alone Medicare prescription drug plan during your Initial Enrollment Period for Part D. You are eligible for drug coverage if:

  • You live in a service area covered by the health plan, and
  • You have Medicare Part A AND/OR Medicare Part B.

Generally, your Initial Enrollment Period for Part D will occur at the same time as your Initial Enrollment Period for Medicare Part B (the seven-month period that starts three months before your eligibility for Part B, includes the month you are eligible, and ends three months later).

Once you are eligible for Medicare Part D, you must either enroll in a Medicare prescription drug plan, Medicare Advantage Prescription Drug plan, or have creditable prescription drug coverage (that is, drug coverage that is expected to pay at least as much as standard Medicare prescription drug coverage). Some people may choose to delay Medicare Part D enrollment if they already have creditable drug coverage through an employer group plan.

However, if you do not sign up for prescription drug coverage when you are first eligible for Part D, you may have to pay a late-enrollment penalty for signing up later if you go without creditable prescription drug coverage for 63 or more consecutive days.

Medicare Part D Annual Election Period:
If you did not enroll in drug coverage during IEP, you can sign up for prescription drug coverage during the Annual Election Period that runs every year from October 15 to December 7.

During AEP, you can:

  • Sign up for a Medicare prescription drug plan.
  • Drop a Medicare prescription drug plan.
  • Join a Medicare Advantage plan that includes prescription drug coverage.
  • Switch from a Medicare Advantage plan that doesn't include drug coverage to a Medicare Advantage plan that does (and vice versa).

Outside of the Part D Initial Enrollment Period and the Annual Election Period, the only time you can make changes to prescription drug coverage without a qualifying Special Election Period is during the Medicare Advantage Disenrollment Period (MADP)--but only if you are dropping Medicare Advantage coverage and switching back to Original Medicare. The Medicare Advantage Disenrollment Period runs from January 1 to February 14.

Medicare Part A and Part B do not include prescription drug coverage, and if you switch back to Original Medicare during the Medicare Advantage Disenrollment Period, you will have until February 14 to join a stand-alone Medicare prescription drug plan.

Medicare Supplement plans enrollment

Medicare Supplement Plans (or Medigap) are voluntary, additional coverage that helps fills the gaps in coverage for Original Medicare. The best time to enroll in a Medicare Supplement plan is during your individual Medigap Open Enrollment Period, which is the six-month period that begins on the first day of the month you turn 65 and have Medicare Part B. If you decide to delay your enrollment in Medicare Part B for certain reasons such as having health coverage based on current employment, your Medigap Open Enrollment Period will not begin until you sign up for Part B.

During your Medigap Open Enrollment Period, you have a "guaranteed-issue right" to buy any Medigap plan sold in your state. This means that insurance companies cannot reject your application for a Medicare Supplement plan based on pre-existing health conditions or disabilities. They also cannot charge you a higher premium based on your health status. Outside of this open enrollment period, you may not be able to join any Medigap plan you want, and insurers can require you to undergo medical underwriting. You may have to pay more if you have health problems or disabilities.

Medigap plans, like Medicare Advantage plans, are offered through private insurance companies, and are available for purchase through brokers like eHealth Insurance Services, Inc.

Do you have more questions? Connect with any of our licensed insurance agents to discuss a Medicare plan that may be right for you.

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