When you turn 65 years old, you become eligible for Medicare – but you’re not automatically signed up. You join during an initial enrollment period, and if you want to make changes to your Medicare selections in the future, you’ll need to wait until specific enrollment periods to do so. This guide outlines the differences between Medicare enrollment periods and what actions are and aren’t allowed in each one.

Initial enrollment period for Medicare Parts A, B, and D

When is the enrollment period for Medicare?

If you’re new to Medicare, plan to enroll around your 65th birthday. The seven months around that milestone are known as your initial enrollment period or IEP. 

Your IEP will begin three months before you turn 65, continue through your birthday month, and end three months later. Yet, if your birthday falls on the first of the month, your IEP will start four months before your birthday month and end two months after it. 

What is allowed during the initial enrollment period?

This is the time to enroll in Medicare Part A (hospital insurance) and/or Part B (medical insurance). You may also get Part D for prescription drug coverage. 

It’s important to sign up during your IEP, if possible, to avoid a penalty for late enrollment. If you enroll late for Part B, you may pay an additional 10% for each year you could’ve had coverage. For example, if you wait three years past your IEP to enroll in Part B, you may have to pay an extra $50 per month — for the life of your Part B coverage. The same penalty may also apply for Part A premiums.

If you or your spouse are still working when you turn 65, you can sign up for Medicare or keep your coverage under your employer's plan. But keep in mind, you’ve been paying into Medicare via payroll deductions, so you may pay no premium if you enroll in Original Medicare Part A (hospital insurance) when you’re first eligible. Visit Medicare’s website to see which processes you’ll need to follow for your particular situation.

When does Medicare coverage begin?

The month your Medicare coverage starts will depend on the part(s) you choose. Yet, your coverage will always begin on the first day of the month. 

For Part A, your coverage will start the month you turn 65. This is unless your birthday is the first day of the month. In that case, it will begin the month before your birthday. 

Your Part B coverage will begin based on the month you sign up. For example, if you turn 65 in May, January through July is your initial enrollment period. If you sign up in the first three months of that period, your coverage will begin May 1. If you sign up during your birthday month or the three months after, your coverage will start the month after you sign up.

General enrollment period

What is the general enrollment period for Medicare?

If you missed your initial enrollment period, the general enrollment period (GEP) gives you another time to sign up for Part B.

When is the general enrollment period for Medicare Part B?

General enrollment takes place Jan. 1 through March 31 every year. 

What is allowed during the general enrollment period?

If you’re unable to qualify for a special enrollment period (details below), you may face a penalty for late enrollment. Currently, you’ll need to pay an extra 10% or more of your monthly premium for the duration of your Part B coverage.

When will Medicare Part B coverage begin under the GEP?

July 1 will be your start date no matter when you sign up during general enrollment.

Special enrollment period

What is a special enrollment period?

You can sign up late for Part B and Premium Part A — with no penalty — when you qualify for special enrollment for these events and others: 

• You’re still working and have group health coverage through your employer.
• You’re performing voluntary service in another country or have TRICARE.
• You were affected by a natural disaster or other emergency.
• You lost Medicaid or other coverage.
• You’ve experienced other life events.

How long is a special enrollment period?

The timing of your special enrollment period will depend on your situation. For example, after you stop working or lose group health coverage, you’ll have eight months to sign up for Medicare. Other situations generally allow you six months to enroll. 

What is allowed during a special enrollment period?

Special enrollment does not apply to COBRA or other retiree coverage outside of Medicare. This means you cannot get a special enrollment period for loss of these plans or extend or pause your enrollment period by adding one of those plans.

Other situations that don’t qualify for special enrollment are loss or replacement of Marketplace coverage or having end-stage renal disease. 

When does coverage begin?

Your coverage start date will depend on your situation but will generally be the month after you sign up. It’s best to enroll during your special enrollment period so that you don’t have to wait for general enrollment and incur a monthly penalty fee.

Annual enrollment period

How long is the annual enrollment for Medicare?

The annual enrollment period for Medicare runs Oct. 15 to Dec. 7 every year.

What is the Medicare annual enrollment period?

Medicare’s annual enrollment period, also known as the open enrollment period or the annual election period, is when you can make changes to existing Medicare coverage. You may choose to:

• Join a Medicare Advantage plan or switch to a different plan.
• Cancel your Medicare Advantage coverage.
• Change your coverage from original Medicare to Medicare Advantage.
• Join a prescription drug plan or change your drug plan.

In the months before annual enrollment, Medicare Advantage plans must share changes to their service area, benefits, premiums, or copayments. This is to ensure you have the chance to get the coverage you need for the following year. 

When will changes to coverage take effect?

Any changes you make to your coverage during the annual enrollment period will go into effect on Jan. 1.

Initial coverage election period (ICEP) for Medicare Advantage, Part C

What is the initial coverage election period for Medicare Advantage, Part C?

If you’re considering a Medicare Advantage plan, the initial coverage election period (ICEP) is your time to enroll.

When is the enrollment period for Medicare Advantage, Part C?

The enrollment period for Medicare Advantage, Part C, is much like the initial enrollment period for Medicare Parts A and B. It begins three months before you turn 65. Yet, depending on your circumstances, your ICEP will end on whichever of these options falls later:

• The last day of your initial eligibility (or IEP) to enroll in Medicare Parts A and B
• The last day of your initial enrollment period for Part B due to delayed enrollment

For example: 

• Your 65th birthday is in May, making you eligible to enroll in Parts A and B from February to August. Your ICEP to enroll in Medicare Advantage, Part C, will follow the same timeline. However, your Medicare Advantage coverage cannot begin before your original Medicare coverage starts. This means, if your original Medicare coverage does not start until June, your Medicare Advantage coverage cannot begin before June. 
• You enroll only in Part A only because you’re still insured under your employer’s group health plan and qualify for a Special Enrollment Period. You retire early the next year and add Part B, which will go into effect on April 1. Your ICEP for Medicare Advantage, Part C, then becomes January through March.  

Medicare Advantage open enrollment period (MA OEP)

What is annual enrollment vs. open enrollment for Medicare Advantage?

During annual enrollment, you can make changes to any Medicare coverage. Yet, the Medicare Advantage open enrollment period (MA OEP) is specific to Medicare Advantage plans. MA OEP falls just after annual enrollment for another opportunity to modify your coverage.

When is open enrollment for Medicare Advantage?

The MA OEP runs Jan. 1 through March 31 every year. 

What is allowed during the MA OEP?

If you’re currently enrolled in a Medicare Advantage plan, you can use this time to select a different Medicare Advantage plan or cancel your Medicare Advantage coverage and opt for original Medicare.

When do MA OEP changes go into effect?

Your new Medicare Advantage plan or original Medicare will go into action the first day of the next month. This means, if you choose a new Medicare Advantage plan in February, it will go into effect March 1.

Supplemental health insurance enrollment

When can I enroll for Medicare Supplement insurance and other supplemental health insurance?

If you’re wondering, “What is the special enrollment period for supplemental health insurance?,” there’s great news. There is no annual enrollment period for supplemental health insurance plans. 

After you turn 65 and sign up for Medicare Parts A and B, you can add Medicare Supplement coverage at any point during the year. But you cannot add Medicare Supplement coverage to a Part C Medicare Advantage plan.

Other supplemental health insurance, such as Dental, Hospital Indemnity, Short-term Care, and First Diagnosis Cancer insurance, can also be purchased any time of the year to help with out-of-pocket expenses from Medicare coverage gaps.

When does coverage begin?

Your coverage start date depends on the type of supplemental health insurance you get and from whom, but generally, it starts on the first day of the next month after you buy a policy.

How can I choose a supplemental health insurance plan?

The Centers for Medicare and Medicaid Services publish an annual Medicare Supplement Buyers Guide that details how to buy a Medigap policy. You can also visit Wellabe’s products page to learn about all of our supplemental health insurance plans, call 877-257-2663 to speak to an agent, or request a personalized, free quote.

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