Medicare Initial Enrollment Period Calculator & Medicare Calculator

Learn when your Medicare Initial Enrollment Period starts with our Medicare Calculator.*
To use our Medicare & Medicare Supplement Calculator, you will need to type in your date of birth into the dedicated bracket. Once you do that, the calculator will automatically provide information regarding your initial starting period.

*The Medicare Initial Enrollment Period is a 7-month window during which you can first sign up for Medicare coverage. The period begins three months before the month you turn 65 and ends three months after the month you turn 65. If your birthday is the first day of the month, your entire enrollment period is moved forward one month. You should enroll in Medicare Part A and B to avoid late enrollment penalties.

Medicare Initial Enrollment Period

Calculate Medicare Supplement
Initial Enrollment Period.

When Do I Become Eligible for Medicare?

You become eligible for Medicare no sooner than the month you turn 65.

The Medicare coverage then starts on the first day of the month of your 65th birthday unless your birthday falls on the first day of the month. If your birthday falls on the first day of the month, the coverage will start on the first day of the month before your 65th birthday.

To qualify for Medicare when you’re 65, you will also need to:

  • Be a U.S. citizen or be a legal U.S. resident for at least five years;
  • Have paid Medicare taxes for a minimum of 40-quarters during your lifetime. Otherwise, you may not qualify for Medicare Part A premium-free insurance.

However, you may also be able to enroll in Medicare before you turn 65. This can happen if:

  • You have been enrolled in the Social Security disability benefit for a minimum of 24 consecutive months;
  • You suffer from permanent kidney failure (ESRD), and your disease requires regular dialysis or a kidney transplant – provided you or your spouse have paid Social Security taxes for a required period;
  • You collect disability pension from the Railroad Retirement Board;
  • You have Lou Gehrig’s disease (amyotrophic lateral sclerosis).

New to Medicare? Learn more about it here.

How Can I Enroll in Medicare?

There are six key Medicare enrollment periods. During these periods, you can join, switch, and drop Medicare and Medicare Advantage plans.

Learn More About Medicare Plans

Initial Enrollment Period

The Initial Enrollment Period style=”font-weight: 400;”> is when you can first sign up for Medicare coverage. Essentially, you have a seven-month window during which you can enroll in Medicare. It starts three months before your 65th birthday month and ends three months after your 65th birthday month.

During your Medicare Initial Enrollment Period, you can:

You can calculate when your Initial Enrollment Period starts using our Medicare Calculator above.

Medicare Supplement Open Enrollment Period

If you want to supplement your Original Medicare to help with additional costs, you can enroll in a Medicare Supplement plan. The best time to do that is during the Medicare Supplement Open Enrollment Period.

It’s a six-month (180-day) period that starts on the first day of the month of your 65th birthday. However, keep in mind that to be eligible for the Medicare Supplement plan, you will first need to enroll in Medicare Part B and Part A.

General Enrollment Period

The General Enrollment Period lasts between January 1 and March 31 each year. During this period, you can sign up for Medicare Part A or Part B if you:

  • failed to join Medicare during the initial enrollment period,
  • aren’t eligible for the special enrollment period.

If you enroll during this period, your health coverage will start on the first day of the month following enrollment. However, bear in mind that you might be subject to late enrollment penalties.

Annual Medicare Enrollment Period

Each year, from October 15 to December 7, any person enrolled in Medicare can change or enroll in the plan. That period is called the Annual Enrollment Period. During it, you can:

  • Switch your Original Medicare plan to a Medicare Advantage plan and vice versa;
  • Change your Medicare Advantage plan with drug coverage to one without and vice versa;
  • Enroll in or drop your Advantage Plan (Medicare Part C) covering prescription drugs;
  • Switch to a different plan offered by your insurer or switch to a new health insurance provider;
  • Enrol in or switch Medicare Part D prescription drug plans.

If you make changes to your current Medicare plan during that period, your new coverage will begin on January 1.

Medicare Advantage Open Enrollment Period

The Medicare Advantage Open Enrollment Period takes place each year from January 1 to March 31. During this period, people with Medicare Advantage can:

  • Decide to change the Medicare Advantage plan with prescription drug coverage to the one without and vice versa;
  • Switch to Original Medicare from Medicare Advantage and enroll in Part D.

Once the change is made, the coverage will start on the first day of the following month. So, for example, if you make a change on January 6, the new coverage will start on February 1.

Special Enrollment Period

The Special Enrollment Period (SEP) allows you to join, switch, or drop your Medicare Advantage or prescription drug Medicare plan outside the standard enrollment periods.

However, to be eligible for the Special Enrollment Period, you must meet several conditions, including:

  • You move back to the U.S. after living abroad;
  • You move out of your current plan’s service area;
  • Your employment plan ends;
  • You move into or out of a psychiatric facility, rehab hospital, long-term care facility, or skilled nursing facility.

In general, if you lose your Medicare coverage through no fault of your own, you will likely be eligible for a Special Enrollment Period.  

Your Special Enrollment Period will be available for a limited time. Once it passes and you have failed to join or switch Medicare plans, you’ll need to wait for the next General Enrollment Period, and you may be subject to late enrollment penalties. 

The Special Enrollment Period also ends once you enroll in your first choice of plans.

What If I Miss the Medicare Enrollment Period Deadline?

There are financial penalties for not enrolling in Medicare when you are supposed to.  You should enroll in your Medicare coverage the moment you become eligible for it, ergo, your Initial Enrollment Period.

If you fail to do that, your next chance to enroll is the Medicare Annual Enrollment Period (October 15 to December 7 each year) or your Special Enrollment Period.

In general, if you fail to enroll during your Initial Enrollment Period, you are likely to be subject to a late enrollment penalty, which typically is a 10% rise in premiums for every 12-month period you could have, but failed to enroll in Medicare Part B.

Use our Medicare Calculator to know when your Initial Enrollment Period starts to ensure you don’t miss it.


What is my Medicare Initial Enrollment Period?

Your Medicare Initial Enrollment Period is a seven-month window beginning three months before the month you turn 65. In other words, you have a seven-month period to enroll in a Medicare plan to avoid paying late enrollment penalties.

How Do I Compare Medicare vs.  My Employer Sponsored Health Plan?

Just as we have a calculator to help you identify your enrollment periods, we have developed a free Medicare vs Employer Plan benefit calculator to help determine which is a better value.  Try it out! 

What is Medicare?

Medicare is the official health insurance provided by the Federal Government to individuals aged 65 and older. It also applies to U.S. citizens younger than 65 with permanent disabilities.

It’s the largest health insurance program in the United States, divided into four parts – A, B, C, and D.

What Medicare plans are there?

Original Medicare is constituted of three plans:

  • Part A: inpatient hospital insurance that helps cover inpatient hospital care, skilled nursing facility care, hospice care, and home health care.
  • Part B: medical insurance that helps cover standard outpatient and physician services, such as outpatient care, medical equipment (wheelchairs, walkers, hospital beds, etc.), or services from doctors and health providers.
  • Part D: drug coverage that helps pay the costs of prescription drugs and medications. You can join it separately in addition to Original Medicare or enroll automatically when you join a Medicare Advantage Plan.

We have numerous articles on this website that detail what Medicare covers. 

Medicare Part C:  Also called Medicare Advantage, is a private alternative to Medicare Part A & B.   It is not really a “part” of Medicare.  It replaces your Original Medicare.  When you enroll in Part C, you are replacing your Original Medicare with an alternate plan administered by an insurance company.

Medigap Insurance:  Medicare Supplemental Insurance, also referred to as Medigap, is an extra insurance policy bought from a private insurer. It helps pay the deductibles, coinsurance and copays of Original Medicare. Medigap policies are named by letters and standardized across the states.  With a Medigap policy you can limit your annual maximum out of pocket costs for Medicare bills to just a few hundred dollars. 

How much does Medicare cost?

When you enroll in Medicare, you will be required to pay monthly premiums. An amount of a monthly premium varies depending on your income, including non-taxable Social Security benefits and tax-exempt interest.

As discussed, the premium will also depend on whether you enrolled in Medicare during your Initial Enrollment Period.

Where can I find more information on Medicare?

Medigap Seminars is your number one online source of Medicare and Medigap information. We’re an independent insurance broker that has won multiple awards from some of the best insurance providers in the country.

However, if you fail to find the information you seek on our site, you should always refer to the official gov websites or simply call us at 800-847-9680.

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