When Are the Medicare Enrollment Periods?

You've probably heard of Medicare Open Enrollment, but did you know that there are 5 different Medicare enrollment periods? Keep reading to learn more about the enrollment periods.

If you want more personalized help with enrolling in Medicare, fill out a call back request form and a licensed insurance agent will get back to you. 

1. Initial Enrollment Period (IEP)

Your Initial Enrollment Period is the first opportunity to sign up for Medicare. It lasts for seven months, starting three months before the month you turn 65, including your birth month, and ending three months after.

• If you enroll before your birthday month, coverage starts on the first day of your birth month.
• If you enroll during or after your birth month, coverage may be delayed.

What You Can Do During IEP:

✅ Sign up for Medicare Part A (Hospital Insurance) and Part B (Medical Insurance).
✅ Enroll in a Medicare Advantage (Part C) plan or a Part D prescription drug plan.

Tip: If you're still working and covered by an employer’s health plan, you may not need to enroll in Part B right away.

2. General Enrollment Period (GEP)

If you missed your Initial Enrollment Period and don’t qualify for a Special Enrollment Period, you can sign up for Medicare during the General Enrollment Period. This runs from January 1 to March 31 each year.

• Coverage starts on July 1 of the same year.
• A late enrollment penalty may apply if you didn’t sign up when first eligible.

What You Can Do During GEP:

✅ Enroll in Medicare Part A and/or Part B.
✅ Sign up for a Medicare Advantage or Part D plan (but only from April 1 to June 30).

3. Special Enrollment Period (SEP)

You may qualify for a Special Enrollment Period if you delayed Medicare due to having creditable coverage, such as employer-sponsored insurance.

• The SEP typically lasts eight months from the time you lose your employer coverage.
• No late enrollment penalties apply if you enroll during this period.

Common Reasons for SEP Eligibility:

✅ You retire and lose employer coverage.
✅ You move out of your plan’s service area.
✅ You qualify for Medicaid or Extra Help with prescription costs.

4. Medicare Advantage Open Enrollment Period (MA-OEP)

This period runs from January 1 to March 31 and applies only to people already enrolled in a Medicare Advantage (Part C) plan.

What You Can Do During MA-OEP:

✅ Switch to a different Medicare Advantage plan.
✅ Drop Medicare Advantage and return to Original Medicare (Part A & B).
✅ Enroll in a standalone Part D prescription drug plan if switching to Original Medicare.

Note: You cannot switch from Original Medicare to Medicare Advantage during this time.

5. Annual Enrollment Period (AEP)

Also known as Medicare Open Enrollment, this period runs from October 15 to December 7 each year.

What You Can Do During AEP:

✅ Switch from Original Medicare to a Medicare Advantage plan (or vice versa).
✅ Change Medicare Advantage plans.
✅ Enroll in, switch, or drop a Medicare Part D prescription drug plan.

Changes take effect on January 1 of the following year.

Avoid Late Penalties & Coverage Gaps

• If you miss your IEP and don’t qualify for an SEP, you could face lifetime penalties, especially for Part B and Part D.
• If you need help choosing the right plan, talk to a licensed Medicare advisor or visit Medicare.gov for official resources.

Let Us Help You

Here at Temecula Medical Group, we want the absolute best care for our seniors. That's why we offer free Medicare Info sessions to 

Understanding your Medicare enrollment periods ensures you get the coverage you need without unnecessary costs. Whether you’re enrolling for the first time or reviewing your options, staying informed helps you make the best choice for your healthcare needs.

Learn More About Medicare

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Temecula Medical Group Place of Healing: We strive to make our clinic a healing space for all of our patients through compassionate care and active listening.