Medicare Enrollment Periods Cheat Sheet for Independent Agents
In short: Medicare has six enrollment windows every agent should know: the Initial Enrollment Period (IEP), the Annual Enrollment Period (AEP, October 15 to December 7), the Medicare Advantage Open Enrollment Period (MA OEP, January 1 to March 31), the General Enrollment Period (GEP), the Medigap Open Enrollment Period and Special Enrollment Periods (SEPs). Knowing which window a client is in tells you what they can change and when coverage starts.
AEP gets the attention, but it’s only eight weeks long. Agents who build steady books work the other 44 weeks too. Turning-65 clients, people leaving employer coverage and clients who move all have their own windows.
Use this cheat sheet to answer one question quickly: “What can this client do right now?”
What Are the Medicare Enrollment Periods?
| Window | Dates | Who it’s for | What they can do |
|---|---|---|---|
| Initial Enrollment Period (IEP) | 7 months: 3 months before the 65th birthday month, that month and 3 months after | People new to Medicare at 65 | Enroll in Parts A and B, plus a Medicare Advantage or Part D plan |
| Annual Enrollment Period (AEP) | October 15 to December 7 | Everyone with Medicare | Join, switch or drop Medicare Advantage and Part D plans; changes start January 1 |
| MA Open Enrollment Period (MA OEP) | January 1 to March 31 | People already in a Medicare Advantage plan | Make one change: switch MA plans or return to Original Medicare and add Part D |
| General Enrollment Period (GEP) | January 1 to March 31 | People who missed their IEP and have no SEP | Sign up for Part A or B; late penalties may apply |
| Medigap Open Enrollment | 6 months, starting the month a client is 65 or older and enrolled in Part B | New Part B enrollees | Buy any Medigap plan sold in their area without medical underwriting |
| Special Enrollment Periods (SEPs) | Varies by event | Clients with a qualifying life event | Join or change coverage outside the usual windows |
People new to Medicare Advantage also get a one-time change during their first 3 months in the plan.
Which Special Enrollment Periods Come Up Most Often?
SEPs keep your calendar full outside AEP. These are the ones agents see most:
- Moving out of a plan’s service area or to a new area with different plan options.
- Losing employer or union coverage. Clients get 8 months to enroll in Part B without a penalty, and a window to choose a plan.
- Medicaid or Extra Help. Eligibility rules for these SEPs changed in 2025, so check current CMS guidance before you enroll a dual-eligible client.
- Moving into or out of a nursing home or other institution.
- A plan leaving the area or a contract ending.
- Five-star plans. Clients can switch into a 5-star Medicare Advantage or Part D plan once between December 8 and November 30.
Always document the SEP reason and keep proof on file. Carriers may ask for it.
How Can Agents Stay Busy After AEP?
The weeks after December 7 are a great time to serve clients and grow. Try these:
- Call every new AEP enrollee in January. Confirm their ID cards arrived, their doctors are in network and their prescriptions filled correctly.
- Use MA OEP carefully. Help clients who are unhappy with a Medicare Advantage choice make their one change. Remember that unsolicited outreach rules still apply.
- Build a turning-65 pipeline. IEP never stops. Our turning-65 enrollment guide walks through each step.
- Work with clients retiring from employer plans. Our post on clients working past 65 covers the timing.
- Round out coverage. Review life, final expense, dental and hospital indemnity needs while you have the client’s attention.
What Happens If a Client Misses a Window?
Missed deadlines can cost clients money for life. Help them understand the stakes.
- Part B late penalty: 10% added to the premium for each full 12-month period they could have had Part B but didn’t.
- Part D late penalty: 1% of the national base premium for each month without creditable drug coverage, added for as long as they have Part D.
- GEP coverage timing: Part B coverage starts the month after they sign up during GEP.
- Medigap underwriting: After the Medigap Open Enrollment window, insurers may review health history unless a guaranteed issue right applies.
How Does Lourie Agent Partners Help You Work Every Enrollment Period?
We help you stay productive all year, not just during AEP.
- Advanced Marketing Program (AMP): Direct-mail lead campaigns for turning-65 prospects, dual and chronic special needs plans, and AEP promotions.
- Free myLourie CRM and enrollment software to track client birthdays, renewals and follow-up dates.
- Training on SEPs and enrollment rules, including in-person workshops and on-demand webinars.
- Extended support hours during AEP, plus after-hours appointment support.
- Direct carrier appointments, commissions paid directly to you and full vesting from day one.
Learn more about our marketing program.
Frequently Asked Questions
AEP (October 15 to December 7) is open to everyone with Medicare. MA OEP (January 1 to March 31) is only for people already in a Medicare Advantage plan, and it allows one change.
Not if they have Original Medicare with a stand-alone Part D plan. MA OEP is only for Medicare Advantage enrollees. They would need AEP or a qualifying SEP.
January 1 of the following year.
Up to 8 months after employment or group coverage ends, whichever happens first. Encourage them to enroll before coverage ends to avoid a gap.
You can help clients who contact you, but CMS limits marketing that targets the MA OEP. Follow CMS marketing rules and carrier guidelines.
A good FMO helps you find turning-65 and SEP opportunities, trains you on the rules and supports you all year. Lourie Agent Partners offers lead programs, training and free CRM tools.
Build a Book That Works All Year
The best agents know every window and use each one to serve clients. Let us help you plan your year. Get contracted with Lourie Agent Partners or call (803) 256-2067.