Whether you are already on Medicare or will be applying for Medicare in the future, there are some key dates to be aware of.

Medicare Initial Enrollment Period

The initial enrollment period (IEP) is your first chance to sign up for Medicare. The IEP usually starts when people turn 65. It lasts for seven months, starting three months before you turn 65 and ending three months after the month you turn 65.

What happens if your birthday falls on the 1st of the month?

Well, your 7-month initial enrollment period starts four months before you turn 65 and ends two months after the month you turn 65. Generally, your coverage will begin on the first day of the month before you turn 65.

For those whose birthdays fall on the first day of the month, Medicare coverage will begin on the first day of the previous month. For example, if your birthday is July 1st when you turn 65, your initial enrollment period is March through September. If you sign up for Medicare in March, April, or May, your coverage starts on June 1st.

Medigap Open Enrollment Period

The ideal time to buy a Medigap policy is during your 6-month Medigap Open Enrollment Period. This period automatically starts the first month you have Medicare Part B, and you are 65 or older. If you get a Medigap policy during this 6-month open enrollment period, you generally will get better prices on Medigap policies. Medigap companies must sell you a policy regardless of your health status, and they cannot deny you coverage.

Medicare Advantage Open Enrollment Period

The Medicare Advantage Open Enrollment Period (OEP) is for current Medicare Advantage plan members and allows a change in Medicare Advantage plans. The timeframe is from January 1st to March 31st of each year.

This period gives you another opportunity to get the coverage you want and need. You can explore other plan options and enroll in a different Medicare Advantage plan. OEP only gives you a one-time change. Remember, you only get this option if you already have a Medicare Advantage plan. You cannot switch from original Medicare and enroll in a new Medicare Advantage plan during the OEP.

You can also drop your Medicare Advantage plan and go back to original Medicare. If you return to original Medicare, you can enroll in Part D prescription drug coverage and apply for a Medigap (aka Medicare Supplement) policy. You will likely have to answer medical underwriting questions, and the company is not required to accept you into the Medigap plan, so if you have any health issues, you might not qualify.

Annual Election Period for Medicare Advantage and Part D Plans

The Medicare Annual Enrollment Period, also called AEP, runs from October 15th to December 7th of each year. Any changes made during AEP will go into effect on January 1st of the upcoming year.

During this time, Medicare beneficiaries have the option to make specific changes:

  • Change to a different Medicare Advantage Plan
  • Move from a Medicare Advantage plan to a Medicare Supplement Plan with a prescription drug plan
  • Join or change Prescription Drug plans
  • Enroll in a Medicare Advantage plan (as long as you have both Medicare Parts A and B)
  • Change from a Medicare Supplement Plan to a Medicare Advantage Plan.

What is the difference between Open Enrollment and the Annual Election Period?

The main difference between Medicare Advantage Open Enrollment and Medicare Annual Enrollment is who can use each one. Medicare Annual Enrollment is when anyone with Medicare can make coverage changes for the upcoming year, while Medicare Advantage Open Enrollment is only for people currently enrolled in a Medicare Advantage plan.

One notable difference between the two is the timing. Medicare Annual Enrollment is from October 15th through December 7th of each year, while Medicare Advantage Open Enrollment is from January 1st – March 31st.

You can learn more about the Open Enrollment Period and the Annual Election period HERE.

Medicare Special Enrollment Periods (SEPs)

Medicare beneficiaries can enroll or change their existing Medicare coverage during a Medicare Special Enrollment Period (AKA Special Election Period AKA SEP)

Some of the life events that will trigger a SEP are:

Move out of Coverage Area

If you’re enrolled in a Medicare Advantage Plan (or Prescription Drug Plan), and you move outside of the plan’s coverage area, you will have a SEP and be required to change plans.

If you tell your current insurance company before your move, your chance to switch plans begins the month before the month you move and continues for two whole months after you move.

If you tell your insurance carrier after you move, your chance to switch plans begins the month you tell your plan, plus two more full months.

If you move within your current plans coverage area, but there are new plans available that weren’t available where you lived before, the same SEP and timeframe apply.

Returning to the USA after living out of the country

If you have been living abroad and you move back to the United States, you’ll get a Special Enrollment Period (SEP) to join a Medicare Advantage plan or a Part D prescription drug plan. Your SEP begins the month before your move and lasts up to two months after the month you move. For example, if you move back to the U.S. in May, your SEP is from April through July.

Losing Employer Insurance

Individuals 65 years of age or older with a current employment-based health plan may not be required to apply for Medicare Part B medical insurance. If you lose employer insurance, you may qualify for the Medicare Part B Special enrollment period. This SEP allows you to delay taking Part B if you have coverage through your or a spouse’s current job. You usually have eight months from when employment ends to enroll in Part B. Coverage that isn’t through a current job – such as COBRA won’t help you qualify, but the SEP lasts for eight months, so you may still qualify if your employment ended recently.

It is vital to establish if your health coverage meets the group health plan coverage criteria defined by the Internal Revenue Service. A group health plan typically provides coverage to employees and their families.

Awareness of the various Medicare enrollment periods is crucial to make appropriate changes or joining plans based on individual requirements. Because the Medicare rules regarding these dates can be confusing, working with a qualified professional is essential.


  • https://www.ssa.gov/help/iClaim_medSEP.html
  • https://www.medicare.gov/sign-up-change-plans/joining-a-health-or-drug-plan/special-circumstances-special-enrollment-periods