Every fall, Medicare opens its biggest window for plan changes: the Annual Enrollment Period, or AEP. It runs from October 15 to December 7 each year, and any changes you make take effect on January 1.
If you are on Medicare, this window matters even in years when you feel happy with your plan. Here is why, and how to use it well.
What You Can Do During AEP
Between October 15 and December 7, you can:
- Switch from one Medicare Advantage plan to another
- Move from Original Medicare to a Medicare Advantage plan
- Leave Medicare Advantage and return to Original Medicare
- Join a Part D prescription drug plan if you did not have one
- Switch from one Part D plan to another
- Drop Part D coverage (be careful: going without creditable drug coverage can trigger a late penalty later)
You can make more than one change during the window. Whatever choice is in place when AEP closes on December 7 is what starts on January 1.
One thing AEP does not control: Medicare Supplement (Medigap) policies. Supplement changes are not tied to the fall window. In Minnesota you can apply for a Supplement at other times of year, though insurers may ask health questions outside protected enrollment situations. Our guide to Minnesota’s unique Supplement plans covers how those work.
AEP vs. the Medicare Advantage Open Enrollment Period
These two windows get confused constantly. They are not the same thing.
| Annual Enrollment Period (AEP) | MA Open Enrollment Period (OEP) | |
|---|---|---|
| Dates | October 15 to December 7 | January 1 to March 31 |
| Who can use it | Everyone on Medicare | Only people already in a Medicare Advantage plan |
| What you can do | Any Advantage or Part D change | One switch: to another Advantage plan, or back to Original Medicare plus a Part D plan |
| Standalone Part D switches | Yes | No, not for people on Original Medicare |
| Takes effect | January 1 | First of the month after the change |
Think of the OEP as a safety valve. If your new Advantage plan turns out to be a poor fit in January, you get one do-over in the first quarter. But if you are on Original Medicare with a standalone Part D plan, the OEP does not let you change anything, so the fall window is your main opportunity.
Why You Should Review Your Plan Every Year
Your plan can change significantly from one January to the next, even if you change nothing. Each fall, plans update their costs and coverage for the coming year: premiums, deductibles, copays, drug formularies, pharmacy networks, provider networks, and extra benefits can all shift.
Plans are required to mail you an Annual Notice of Change (ANOC), which arrives around September. It lists exactly what will be different in your plan next year. Most people never open it. The people who do sometimes discover that a medication is moving to a more expensive tier, a clinic is leaving the network, or a benefit they use is shrinking.
An annual review does not mean an annual switch. Plenty of our clients review their options and stay put. The point is deciding to stay, rather than drifting into a plan year with changes you never saw coming.
How to Prepare for AEP
A little preparation in September and early October makes the window easy:
- Read your Annual Notice of Change. Note anything that got more expensive or disappeared.
- Update your medication list. Include dosages and how often you fill each one.
- List your must-keep providers. Doctors, clinics, and the hospital you prefer.
- Note your pharmacy preference. Pharmacy networks affect what you pay for the same drug.
- Think about the year ahead. A planned surgery, new diagnosis, or a move changes what matters in a plan.
- Get a comparison done. A licensed agent can line up your current plan against the alternatives for the coming year at no cost to you.
If you are new to Medicare rather than reviewing an existing plan, start with our turning 65 checklist instead. Different windows apply to first-time enrollment.
Common AEP Mistakes to Avoid
- Ignoring the ANOC and finding out about changes at the pharmacy counter in January
- Choosing on premium alone. A low monthly premium can cost more overall once copays, deductibles, and drug tiers are counted
- Forgetting the drug plan. Part D formularies change every year, and last year’s cheapest plan for your medications may not be next year’s
- Missing December 7. After the deadline, your options narrow sharply until the following fall
- Waiting until the last week. Late-window rushes leave no time to fix problems or think choices through
Get a No-Cost AEP Review
Every fall we sit down with Minnesotans, review their ANOC, and compare their plan against what is available for the coming year. Sometimes the answer is switch, and often it is stay. Either way, you head into January knowing what your coverage will do. There is no fee for the review and no obligation. Schedule yours, visit our Medicare plans page, or call (320) 448-8232.