A Guide To Medicare Enrollment Periods

Updated: Jul 17, 2022

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Medicare is the basis for elderly healthcare in America. It’s an expansive program that has lots of constants, from premiums on various parts of the program to what type of services you can get from Medicare. One thing that varies in the Medicare program are the enrollment periods of when people apply for it.

Medicare Enrollment Period

While (almost) everyone can get Medicare when they turn 65, everyone obviously doesn’t turn 65 at the same time. And on top of that, not everyone applies for Medicare at the same time.

Let’s discuss when you, as an individual, can enroll in Medicare, what happens if you miss the initial period of enrollment, and what happens when you want to switch plans. But first, we need to make sure we know what Medicare entails.

  • Elderly people (65 and above)
  • Those suffering from end stage renal disease (kidney failure) or amyotrophic lateral sclerosis, also known as ALS or Lou Gehrig’s Disease
  • Disabled people younger than 65 who collect Social Security Disability Insurance

Medicare is the basis for elderly healthcare in America.

More than 55 million people get Medicare benefits every year, and, as of 2017, the federal government spent more than $700 billion on the program (about $14,000 per person who receives the benefits).

Medicare is split into four main parts. These parts are:

Part A

Covers in-patients healthcare costs like hospital stays, hospice care, skilled nursing care, and more. While there is usually no premium for these services, there is typically a deductible you need to reach before Medicare takes over.

Part B

Covers outpatient costs including doctors’ visits, second opinions, medical equipment, and more. It comes with a monthly deductible of $134.

Part C

Allows you to go outside of the government-developed plan to help find coverage that best fits you. You find a plan through a private insurer and pay a premium for that plan. It covers everything Part A and B covers, as well as often covering Part D costs. They also might include dental, vision, and hearing coverage. These plans are called Medicare Advantage Plans.

Part D

Covers your prescription drug costs. You find a plan with a private insurer approved by Medicare and pay a small premium per month for your coverage.

When it comes time to enroll in these programs, you choose varying combinations to fill your needs. You always start with Part A (because there’s no premium for it) and add more coverage to your plan.

More than 90 percent of Medicare recipients have Part B, and about the same have Part D. Most of the remaining percentage of potential Part D recipients likely get coverage through their Part C plan.

Applying for parts A and B of Medicare, which we’ll refer to as Original Medicare, has varying periods of enrollment depending on your age and when you want to cash in on the benefits.

couple seeking medical advice

The initial enrollment period is the period in which you are first eligible to apply for all parts of Medicare. 

Let’s discuss each enrollment period for these parts of Medicare.

Initial Enrollment Period

This is the most important section going forward. The initial enrollment period (IEP) is the period in which you are first eligible to apply for all parts of Medicare. This period spans seven months, lasting from the three months before your birthday, your birthday month, and the three months after your birthday month. For example:

  • If you were born on July 25 (or any time in July), your IEP starts April 1 and ends October 31.
  • If you were born December 2 (or any time in December), your IEP starts September 1 and ends March 31.

Every other enrollment period will come back and reference your initial enrollment period.

How soon you apply for Medicare within your IEP affects when the start of your Part B coverage starts. For example, if you delay your enrollment until a month after you turn 65, you will have to wait until two months after you enroll to get your coverage.

Let’s go through the list of periods you enroll and when your coverage kicks in:

  • If you enroll in the three months before your birthday month, your coverage starts the 1st of your birthday month.
  • If you enroll during your birthday month, your coverage starts the 1st of the next month after your birthday.
  • If you enroll one month after your birthday month, your coverage starts two months after you enroll.
  • If you enroll two months or three months after your birthday month, your coverage starts three months after you enroll.

If you don’t apply during your IEP, there are other periods that you can apply. But these periods may come with late-enrollment fees for not applying when you were first eligible. Now come the other periods.

Special Enrollment Period

You won’t always need or want Medicare the day you turn 65. One of the more common instances is when you’re still receiving insurance through an employer. (This employer or union must have more than 20 employees/unions.) If this is the case, then you’re allowed a Special Enrollment Period (SEP) for when you decide to make the switch to Medicare.

The enrollment period for this situation is either:

  • While you’re still with the employer: you may decide it’s more cost efficient to use Medicare
  • Up to eight months after the coverage from the employer ends: remember that this time period is only for parts A and B

This period also applies if you are insured by a spouse’s insurance.

medicare fraud

General Enrollment Period

If you missed either or both the IEP and SEP, you still have time to apply for Medicare. This enrollment period is called the General Enrollment Period. It lasts from January 1 to March 31. Your coverage will then begin July 1.

If you missed either or both the IEP and SEP, you still have time to apply for Medicare.

If you apply for Medicare during this time, you will most likely have to pay a late-enrollment fee for Part B. If you do get Part B, this fee will be even higher if you wait until another enrollment period to apply for it.

Open Enrollment Period

This period allows you to change your coverage, meaning you already need to have coverage to be eligible for this enrollment period.

The Open Enrollment Period (OEP) lasts from October 15 to December 7. You coverage for any changes made during this period take effect January 1 of the following year.

During this time, you can:

  • Switch from a Part C plan to an Original Medicare Plan
  • Switch from an Original Medicare Plan to a Part C plan
  • Change your Part C plan
  • Change your Part D prescription plan (to another Part D plan or to one included in Part C)

You are not restricted from dropping any coverage until this period—only changing. Although, you must remember the consequences of late fees for disenrolling then re-enrolling at a later date (the General Enrollment Period). You can drop coverage at any time by contacting your local Social Security office.

Many of the Medicare Advantage enrollment periods are similar to Original Medicare.

For instance, you can first apply for a Medicare Advantage plan at the same as an Original Medicare plan. This is during your Initial Enrollment Period—the three months before and after your birthday, and your birthday month.

You can first apply for a Medicare Advantage plan at the same as an Original Medicare plan. 

You can change from a Medicare Advantage plan to Original Medicare during two periods:

  • During the Open Enrollment Period
  • During the Medicare Disenrollment Period, which lasts from January 1 to February 14

The Special Enrollment Period—when you’re already insured by an employer at 65 years old—is different for Part C than it is for parts A and B. Rather than the eight months allotted for parts A and B, you will have 63 days (basically two months) to apply for Part C from the day your coverage ends.

The Initial Enrollment Period for Part D is the same time as parts A and B. The General Enrollment Period is the same, too, and you’ll have to have parts A and B in order to get Part D. You will have a late-enrollment fee attached to your plan if you get Part D after the IEP.

If you are receiving health insurance through a private employer (with more than 20 employees) or union after age 65, your Special Enrollment Period for when you can apply for Part D is the same as Part C—-63 days after your coverage with the employer ends.

There are some situations where your SEP can come to surface. These situations include:

  • If you move out of your coverage area
  • You enter or leave a nursing home
  • If you qualify for Extra Help on your prescriptions
  • If your plan changes and no longer offers coverage in your area

In any of these cases, you will have 63 days after the trigger date to change your plan.

You can also change your Part D plan during the Open Enrollment Period.

When Can I Enroll In Medigap Plans?

What is Medigap Insurance?

The last group of enrollment periods come with Medigap—the supplemental plans that help pay for everything not covered by parts A and B of Medicare, such as copayments, deductibles, coinsurance payments, and more.

Your first enrollment period to get Medigap—the Medigap Open Enrollment Period—is six months after you turn 65 and/or your Part B coverage kicks in, according to the Medicare website.

Your first enrollment period to get Medigap is six months after you turn 65 and/or your Part B coverage kicks in.

It’s highly encouraged you apply for Medigap during this period because insurance companies won’t be able to use your past medical history (underwriting) to approve or deny your coverage. However, if you apply after the six-month period, companies may deny you coverage or boost your rates based on your medical history.

If you want to switch from a Medigap plan to a Medicare Advantage plan (you can’t have both), you can do so during the Open Enrollment Period. Just notify your care provider that you’re dropping Medigap, then switch your Original Medicare plan to a Medicare Advantage plan.

You can change from a Medicare Advantage plan to a Medigap plan (along with Original Medicare) if you do so within 12 months of initially enrolling in Medicare Advantage. You can also pick up a Medigap plan if you’re moving outside of your Medicare Advantage plan’s area.

If you have any questions regarding your enrollment periods for Medicare- or Medigap-related policies, contact your local Social Security office or visit the Medicare website.

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