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Don’t Miss Your Window: Understanding Medicare Enrollment
Last Updated: June 2025 Print This Article
Timing matters when it comes to Medicare. From your first chance to enroll to opportunities to make changes later, it’s important to know what each enrollment period means—and how to take action when it’s time. Here’s what you need to know to stay on top of the process.
Initial Enrollment Period (IEP)
Use this seven-month window to enroll in Medicare for the first time.
Your Options During the IEP
- Enroll in Original Medicare (Parts A and B).
- Join a Medicare Advantage plan (requires enrollment in Parts A and B).
- Enroll in a Medicare prescription drug plan (Part D).
If you’re interested in a Medicare Supplement (Med Supp) plan, you have a six-month enrollment period beginning the first day of your birthday month. You must sign up for Medicare Part B first. Keep in mind that you can sign up for a Med Supp plan at any time, but if you missed the six-month enrollment period, you could be denied or charged more because of your health history.
Notes:
- If you want to enroll in a Medicare Advantage or Part D plan after the IEP, you can sign up during the Annual Enrollment Period.
- If you didn’t sign up for Parts A and B during your IEP, you can enroll during the General Enrollment Period from January 1 to March 31.
- If you have a premium for Part A and don’t sign up when you’re first eligible, you may have to pay a late enrollment penalty.
- If you don’t use the IEP to sign up for Parts B and D and don’t have other creditable coverage, you may have to pay a late enrollment penalty.
Special Enrollment Period (SEP)
Join a Medicare Advantage plan outside of standard enrollment windows—if you qualify.
Common Special Enrollment Periods
You might qualify for an SEP if you:
- Moved out of your plan’s service area
- Recently lost Medicaid eligibility
- Lost your current coverage
- Joined or didn’t join a plan because of false information from a federal employee
Special enrollment opportunities aren’t limited to what’s shown above. For questions about your unique situation and if you might qualify, call a licensed Essence Healthcare advisor at the number listed at the bottom of this page.
5-Star Special Enrollment Period
Take this opportunity to experience the exceptional service and benefits of a 5-star Medicare plan. Every year, Medicare evaluates plans based on things like customer service, member experience and benefits. Plans are rated using a 5-star scale, with 1 being “poor” and 5 being “excellent.” If there’s a plan with a 5-star overall rating in your area, you may be able to switch outside of standard enrollment windows.
More About the 5-Star SEP
- You can join a 5-star Medicare Advantage plan (with or without drug coverage), a Part D prescription drug plan or Medicare cost plan.
- You may only use this SEP once from December 8 to November 30.
- You don’t qualify to switch plans if you’re already in a 5-star plan.
Annual Enrollment Period (AEP)
Switch, drop or join a different Medicare plan once during this yearly enrollment window.
Your Options During the AEP
- Switch, drop or join a Medicare Advantage plan.
- Switch to a Medicare Advantage plan from Original Medicare or vice versa.
- Add or drop Part D prescription drug coverage.
Medicare Advantage Open Enrollment Period (MA OEP)
Make a one-time election to change your Medicare Advantage plan.
Your Options During the OEP
- Switch to a different Medicare Advantage plan with or without drug coverage.
- Go back to Original Medicare.
- Add or drop Part D prescription drug coverage.
Please note that the MA OEP is only available if you’re already in a Medicare Advantage plan.
How to Enroll
Parts A and B:
To sign up, you’ll need to contact Social Security.
- Online: at SSA.gov
- By phone: 1-800-772-1213 (TTY: 1-800-325-0778).
- In person at your local Social Security office
If the Social Security Administration needs more information, they’ll contact you directly.
Extra Coverage (Medicare Advantage, Med Supp or Part D):
- Contact the company directly, or use their website to enroll.
- Talk to an insurance broker.
- Sign up through Medicare.gov. Note that, while you can compare Med Supp options on this site, you must contact the plan directly to enroll.
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