Enrollment Periods

Medicare has certain times of year when you can sign up or make changes to your plan. Missing these dates can lead to penalties or gaps in coverage. We’ll help you keep track so you can enroll on time and avoid costly mistakes.

Don’t Miss Out: Key Medicare Enrollment Periods You Need to Know

Medicare comes with important deadlines—and missing them can cost you big in the form of penalties or gaps in your health coverage, especially for Part B and Part D. Whether you're just turning 65 or already enrolled and thinking about making changes, it’s crucial to understand when you can take action.

This guide breaks down the main Medicare enrollment periods in simple terms, so you know exactly what to do—and when.

1. Initial Enrollment Period (IEP)

If you're approaching your 65th birthday, this is the most important window to understand. Your Initial Enrollment Period is a 7-month timeframe that starts three months before your birth month, includes your birth month, and continues for three months after.

This is your first chance to enroll in Medicare Parts A and B. If you miss this window and don't qualify for a Special Enrollment Period, you could face late penalties that last the rest of your life.

Example: If your 65th birthday is in June, your IEP runs from March 1st to September 30th.

Note: If your birthday falls on the first day of the month, your coverage and IEP begin one month earlier.

Auto-Enrollment Clarity: If you're already receiving Social Security benefits for at least 4 months before turning 65, you're typically auto-enrolled in Parts A and B. If not, you need to sign up manually through the Social Security Administration (SSA).

2. General Enrollment Period (GEP)

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

However, coverage won’t begin until July 1. This means you will have a gap in coverage from your eligibility date until July 1, and you will likely face late enrollment penalties for Part B and Part D that increase the longer you delay.

3. Annual Enrollment Period (AEP)

The Annual Enrollment Period (also called the Annual Election Period or AEP) happens every year from October 15 to December 7. During this time, anyone with Medicare can:

Switch from Original Medicare to a Medicare Advantage Plan (Part C).
Switch from a Medicare Advantage Plan back to Original Medicare.
Change or enroll in a Part D prescription drug plan.

Changes you make during AEP go into effect on January 1 of the following year.

4. Medicare Advantage Open Enrollment Period (MA OEP)

If you already have a Medicare Advantage Plan (Part C), there's an extra window just for you from January 1 to March 31. During this time, you can:

Switch to a different Medicare Advantage Plan.
Go back to Original Medicare (and add a stand-alone Part D plan if needed).

You can only make one change during this period.

5. Special Enrollment Periods (SEP)

Life happens, and Medicare gets that. Special Enrollment Periods are triggered by specific events that allow you to enroll outside of the regular periods without facing penalties.

SEPs are most commonly triggered by:

Losing employer coverage (or ending coverage from your employer, or your spouse's employer, where you worked past age 65).
Moving out of your plan’s service area.
Qualifying for Medicaid or Extra Help.
Being affected by a natural disaster or emergency.

Crucial SEP Detail: For those losing employer coverage, the SEP to enroll in Part A/B is generally 8 months from when the coverage or employment ends. However, you only have 63 days from the loss of coverage to enroll in a Part D plan to avoid the Part D penalty.

Avoiding Common Pitfalls

Many people assume they can change Medicare plans anytime—but that’s simply not the case. Others miss their Initial Enrollment Period because they're still working and don't realize their employer plan requires them to enroll in Medicare at 65.

Unfortunately, late enrollment penalties for Part B (a permanent 10% increase for every full 12-month period you delayed enrollment) and Part D are permanent and add up quickly. That’s why it’s so important to understand these windows and plan ahead.

Need Help Navigating Enrollment?

Licensed Medicare agents Jim Cable and Steve Milton are here to help you avoid mistakes, understand your options, and enroll on time

Whether you’re turning 65 soon or thinking about switching your current plan, Jim and Steve offer free, personalized guidance to help you:

Track the right enrollment period for your unique situation.
Determine if your current employer coverage is "creditable" to avoid Part D penalties.
Understand what changes you can make (and when).
Avoid penalties and coverage gaps.

Take the Stress Out of Medicare

You don’t have to keep track of all these dates alone. Let our trusted local agents make Medicare easy for you.

Contact Jim Cable or Steve Milton today to schedule your free Medicare consultation and stay on the right track.

FAQ's

Frequently Asked Questions

Q: When should I sign up for Medicare?

Most people sign up when they turn 65. Your Initial Enrollment Period lasts for 7 months — 3 months before your birthday month, your birthday month, and 3 months after.

Q: What happens if I miss my Medicare enrollment window?

If you miss your Initial Enrollment Period, you may face late penalties and gaps in coverage. The good news is, we can review if you qualify for a Special Enrollment Period.

Q: What’s the difference between Medicare Advantage and Medicare Supplement?

Medicare Advantage (Part C) is an all-in-one alternative to Original Medicare that may include extra benefits. Medicare Supplement (Medigap) works alongside Original Medicare to help pay out-of-pocket costs.

Q: Do I need a prescription drug plan?

Yes, unless you already have creditable drug coverage. Medicare Part D helps cover prescription costs — and enrolling on time avoids late penalties.

Q: Will I be able to keep my doctor?

That depends on the type of plan you choose. Some plans have networks, while others let you see any provider who accepts Medicare. We’ll help you find a plan that works with your preferred doctors.

Q: Can I change my Medicare plan later?

Yes — you can review and switch plans during the Annual Enrollment Period each fall, or in certain cases with a Special Enrollment Period.

We provide reliable Medicare guidance designed to give you peace of mind. At Senior Health Insurance, we help secure your future—so you can focus on what truly matters.