Key Takeaways
- The fall Medicare Open Enrollment window (often called AEP) runs October 15–December 7 each year; changes you make during this time usually take effect January 1 of the next year, per Medicare.gov.
- If you are already in a Medicare Advantage plan, the Medicare Advantage Open Enrollment Period runs January 1–March 31 each year, but you can only make limited types of changes—not the same menu of options as fall Open Enrollment (Medicare enrollment periods guide — PDF).
- Special Enrollment Periods (SEPs) may open when you have certain life events (for example, moving or losing other coverage); rules depend on the event, so verify your situation on Medicare.gov.
- If you are reading this in spring 2026, the Medicare Advantage Open Enrollment Period for this year has already ended (March 31)—your next scheduled chance for broad Medicare Advantage and Part D changes is usually October 15–December 7, 2026, unless you qualify for an SEP.
- For Brooklyn and NYC, free help is available through SHIP (SHIP Help); a licensed advisor can explain options among plans available in your area.
- Why Medicare Uses Different Enrollment Windows
- Fall Open Enrollment (AEP): October 15–December 7
- Medicare Advantage Open Enrollment: January 1–March 31
- Special Enrollment Periods (SEPs)
- Quick Comparison: AEP vs Medicare Advantage Open Enrollment vs SEP
- What This Means for NYC Beneficiaries Right Now
- Frequently Asked Questions
- Take the Next Step
Medicare splits enrollment into specific periods so beneficiaries have predictable chances to compare plans—while also allowing mid-year changes when something important changes in your life. Original Medicare (Parts A and B) enrollment follows its own rules (for example, when you are first eligible around age 65), while Medicare Advantage (Part C) and Part D drug plans add fall Open Enrollment, the Medicare Advantage Open Enrollment Period, and Special Enrollment Periods. The details below focus on plan changes most New York City readers ask about; always confirm your personal dates using official Medicare tools because your situation may add extra rules or exceptions.
If you are new to Part C in general, our Medicare Advantage overview explains how these plans work before you worry about calendars.
Fall Open Enrollment is the annual window when most people with Medicare can review and change Medicare Advantage and Part D coverage. On Medicare.gov — Open Enrollment, Medicare states Open Enrollment runs October 15 through December 7 and that changes take effect January 1 of the next year (the plan must get your request by December 7). During this period you may be able to join, switch, or drop a Medicare Advantage plan (with or without drug coverage), switch drug plans if you are in Original Medicare, or move between Original Medicare and Medicare Advantage—depending on what you have now.
This window is what many brokers and articles call the Annual Enrollment Period (AEP) or Annual Election Period. The name on Medicare.gov is Open Enrollment, but the dates are the industry-standard October 15–December 7 reference point for “Medicare plan shopping season.” Use the official Plan Compare tool to see what is offered in your ZIP code; benefits and networks change each year, so even if you like your current plan you should still read your Annual Notice of Change (ANOC).
For a practical prep list, see our Medicare enrollment checklist.
The Medicare Advantage Open Enrollment Period is a separate winter window only for people who already have a Medicare Advantage plan. According to Medicare’s enrollment publication (Understanding Medicare Advantage & Medicare Drug Plan Enrollment Periods), this period runs January 1 through March 31. During this time you cannot use it to switch from Original Medicare into Medicare Advantage if you are not already in a Medicare Advantage plan—eligibility to use the period is tied to already being enrolled in Medicare Advantage as of the start of the year.
What you may be able to do during this period is still limited. The same Medicare guide explains that people in Medicare Advantage during this window can generally make certain changes such as switching to another Medicare Advantage plan or dropping Medicare Advantage and returning to Original Medicare (often with a path to add a standalone Part D plan if you are making that kind of change). The publication also notes you generally cannot switch from Original Medicare to Medicare Advantage during this period, and you cannot use this period to join a standalone Part D plan if you are in Original Medicare—those moves typically wait for fall Open Enrollment unless you qualify for a Special Enrollment Period.
Because rules are easy to mix up, use Medicare’s official page on when you can join, switch, or drop a plan before you assume a change is allowed.
Illustration only—always confirm your personal election periods on Medicare.gov.
A Special Enrollment Period is a window tied to a qualifying event—for example, moving outside your plan’s service area, losing employer coverage, or certain changes in Medicaid or Extra Help status. SEPs are not one-size-fits-all: the length of the window and what you are allowed to do depend on the event. Medicare maintains the authoritative list and timing rules; start with When can I join, switch, or drop a plan? and follow the prompts that match your situation.
If you are dual-eligible (Medicare and Medicaid) and your Medicaid level changes, that may affect which plans you can keep—especially D-SNPs (Dual Eligible Special Needs Plans). Our D-SNP guide for New Yorkers explains how coordination works at a high level; your next step is usually to confirm Medicaid status with New York and then check Medicare election options.
Need help choosing a plan? Call SJM Cares at (347) 696-6757 for a free, no-obligation consultation with a licensed Medicare advisor in Brooklyn.
| Topic | Fall Open Enrollment (often called AEP) | Medicare Advantage Open Enrollment | Special Enrollment Period (SEP) |
|---|---|---|---|
| Typical dates | Oct 15–Dec 7 (each year) | Jan 1–Mar 31 (each year) | Varies by qualifying event |
| Who it is for | Most people with Medicare reviewing Part C / Part D options | People already in a Medicare Advantage plan | People who experience a qualifying life/event rule listed by Medicare |
| Breadth of changes | Broad plan shopping window for Medicare Advantage and Part D (per Medicare.gov) | Limited changes while in Medicare Advantage (enrollment periods PDF) | Depends on the SEP—follow Medicare’s rules for your event |
| Official starting point | Open Enrollment | Enrollment periods PDF | Join, switch, or drop a plan |
This table is a simplified overview. Medicare’s materials are the final word, and some plan types (for example, certain Medicare Medical Savings Account plans) have extra restrictions mentioned in Medicare’s enrollment publications.
If you are in New York City—Brooklyn, Queens, Manhattan, the Bronx, or Staten Island—the same federal Medicare election calendars apply. Local factors (plan availability by county, Medicaid programs, and which carriers serve your ZIP code) affect which plans you can choose, not the national Medicare dates themselves.
Between April and September, many people are outside the fall Open Enrollment window and outside the Medicare Advantage Open Enrollment Period. In that situation you usually wait for October 15 unless you qualify for an SEP or you are in a different enrollment type entirely (for example, your personal Initial Enrollment Period when you are new to Medicare). If your health or coverage needs changed, do not guess—check Medicare’s SEP rules or speak with SHIP for unbiased help (SHIP Help).
Our Community Resource Hub also lists local and state programs that can help with non-Medicare needs while you sort out coverage.
Often, yes. Many licensed agents use AEP to mean the October 15–December 7 window when people with Medicare can make broad changes to Medicare Advantage and Part D coverage. Medicare.gov calls this window Open Enrollment and confirms the October 15–December 7 dates and January 1 effective date pattern.
Usually not during the Medicare Advantage Open Enrollment Period if you are in Original Medicare—that winter window is for people already enrolled in a Medicare Advantage plan to make certain limited changes. To move from Original Medicare into Medicare Advantage, you typically use fall Open Enrollment or a Special Enrollment Period if you qualify. Verify your options using Medicare’s plan change page.
The dates repeat each calendar year: January 1 through March 31, for people who are already in a Medicare Advantage plan, according to Medicare’s enrollment periods publication (PDF). The rules about what you can change are limited compared with fall Open Enrollment.
You may still have options if you qualify for a Special Enrollment Period or if you are approaching your personal Initial Enrollment Period when first signing up for Medicare. Medicare.gov explains qualifying events and timing. You can also call 1-800-MEDICARE or your State Health Insurance Assistance Program (SHIP) for help understanding your specific case.
A move can trigger an SEP when it affects your plan’s service area or your plan options, but not every address change works the same way. Report moves to Medicare and your plan, then follow Medicare’s guidance for your situation. When in doubt, use the official Medicare tools or SHIP rather than informal advice.
Start with the official Medicare Plan Compare tool at Medicare.gov. For unbiased counseling, contact SHIP (find help in your state). If you want to review options among plans we offer in your area, you can also speak with a licensed SJM Cares advisor—see below.
Medicare enrollment calendars are strict, but you do not have to decode them alone. If you want a licensed professional to walk through plan types, networks, and drug coverage for options available where you live, SJM Cares is based in Brooklyn and serves NYC families every week.
Call us at (347) 696-6757 or schedule an appointment online.
Written by Hamad Amir, licensed insurance agent and founder of SJM Insurance Services, LLC. Licensed in New York and New Jersey (License #LB-1024797). Specializing in Medicare Advantage and D-SNP plans for Brooklyn and NYC residents.
Disclaimer: This article is for educational and informational purposes only and does not constitute professional insurance, financial, or legal advice. For personalized guidance, call a licensed SJM Cares advisor at 917-373-0117.
We do not offer every plan available in your area. Currently we represent 10 organizations which offer Medicare Advantage HMO, PPO, PFFS, and PDP plans in your area. Please contact Medicare.gov, 1-800-MEDICARE (TTY: 1-877-486-2048), or your local State Health Insurance Assistance Program (SHIP) to get information on all of your options.
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