AEP Guide: Stay or Switch?
Once a year, you get to make sure your Medicare coverage still fits your life. Most people don't — their plan just quietly renews. Here's how to know if this is the year to take a closer look.
The Part Most People Miss
If you do nothing during AEP, your current plan generally renews automatically. That sounds convenient — but it also means your plan can change substantially for the new year without you ever explicitly agreeing to it. Premiums, which drugs are covered, which doctors are in-network, and what you pay out of pocket can all shift, even if the plan's name stays exactly the same.
Every plan is required to send an Annual Notice of Change (ANOC) letter each September, spelling out exactly what's different for the coming year. It's easy to set aside and forget. Not reading it is the single most common reason people end up with coverage that doesn't actually fit anymore.
Does Any of This Sound Like You?
Tap anything that applies. There's no scoring, no right answer — just an honest look at whether this is a year worth reviewing more closely.
Even checking one of these is a good enough reason to take a closer look before December 7 — plans change quietly, and the review costs you nothing but a conversation.
Get a No-Cost Plan Review →What AEP Actually Lets You Change
AEP covers Medicare Advantage and Part D specifically. A few important things fall outside it.
✅ You Can
- ✓ Switch from Original Medicare to a Medicare Advantage plan
- ✓ Drop Medicare Advantage and return to Original Medicare
- ✓ Switch from one Medicare Advantage plan to another
- ✓ Join, drop, or switch a standalone Part D drug plan
- ✓ Switch to a Medicare Advantage plan with or without built-in drug coverage
❌ You Can't
- ✗ Enroll in or switch a Medigap supplement through AEP — that runs on its own separate rules, and outside your one-time guaranteed-issue window it can involve medical underwriting
- ✗ Drop Medicare Part B entirely — that's a separate process through Social Security, not something AEP covers
- ✗ Enroll in an employer group plan or COBRA through AEP — those follow their own separate enrollment rules
Thinking About Leaving Medicare Advantage for Medigap? Read This First
During AEP, you're free to leave Medicare Advantage and return to Original Medicare, generally effective January 1. But there's a catch a lot of people don't find out about until it's too late: leaving Medicare Advantage and qualifying for a Medigap policy are two separate things.
The right to leave Medicare Advantage and return to Original Medicare, effective January 1.
Automatic guaranteed-issue rights to buy a Medigap policy. Those come from separate, specific protections — not from AEP itself.
If you've been on Medicare Advantage for a while and don't have one of those specific protections, a Medigap insurer is generally allowed to medically underwrite your application — and could charge you more or decline coverage entirely.
If you're outside a guaranteed-issue window and don't otherwise qualify, a Medigap company may require medical underwriting — and you could potentially be denied. Applying for Medigap first can tell you whether you qualify before you give up your Medicare Advantage coverage. Never disenroll from Medicare Advantage just to "see what happens" — always use an actual enrollment period or qualifying Special Enrollment Period.
Want to Switch from Medicare Advantage to Medigap?
Check your eligibility to leave Medicare Advantage during AEP or another applicable enrollment period.
Apply for Medigap first if medical underwriting may apply to your situation.
Wait for the Medigap decision before making any changes to your current coverage.
Confirm your Medigap effective date once you're approved.
Leave Medicare Advantage through the appropriate enrollment period, timed around that date.
Transition to Original Medicare + Medigap, adding a Part D plan alongside it.
You May Have Guaranteed-Issue Rights
Some situations come with federal protections that let you buy a Medigap policy without medical underwriting. A few common examples:
- Trial rights — if you joined Medicare Advantage when you first became eligible for Medicare, or dropped a Medigap policy to try Medicare Advantage for the first time, you generally have a window after enrolling to change your mind and return to Medigap without underwriting.
- Your plan leaves Medicare or your area — if Medicare Advantage stops being offered where you live, that's generally treated differently than a voluntary switch.
- Other qualifying circumstances — several other specific situations can also trigger this same kind of protection.
These are specific, defined situations — not a general guarantee that applies to everyone leaving Medicare Advantage. Your own situation matters here, so it's worth verifying your actual guaranteed-issue eligibility before making any change.
Does This Apply to You?
Tap anything that's true for you.
Medicare rules and individual circumstances vary — this is general information, not a guarantee of your own eligibility. Verify your specific guaranteed-issue rights before making any coverage change.
How the Timeline Actually Unfolds
Your ANOC Letter Arrives
Your current plan mails you an Annual Notice of Change, detailing every change for next year — premiums, formulary, network, and benefits. This is the single most important piece of mail you'll get all year regarding your coverage.
Next Year's Plans Become Visible
Medicare's own plan comparison tools update with the following year's options, so you can start comparing before AEP officially opens.
AEP Opens
You can now actually make changes — switch plans, add or drop Part D, move between Original Medicare and Medicare Advantage.
AEP Closes
The window shuts at 11:59 PM in your local time zone. After this, you're generally locked in until the next enrollment opportunity.
Changes Take Effect
Whatever you chose during AEP — or didn't choose, if your plan simply renewed — becomes your actual coverage for the new year.
AEP vs. the Medicare Advantage Open Enrollment Period
A different, more limited window exists every January through March — it's often confused with AEP, but the rules aren't the same.
| Consideration | AEP (Oct 15 – Dec 7) | MA Open Enrollment (Jan 1 – Mar 31) |
|---|---|---|
| Who it's for | Anyone on Medicare | Only people already on Medicare Advantage |
| Switch Original Medicare ↔ Advantage | Yes, either direction | Only Advantage → Original Medicare |
| Switch between Advantage plans | Yes | Yes, one time |
| Add or change standalone Part D | Yes | Only if also returning to Original Medicare |
| Number of changes allowed | As many as you want | One |
Not Sure Where You Stand?
A PharmSurance advisor with a pharmacy background can walk through your actual plan, your actual medications, and your actual doctors — and tell you plainly whether staying or switching makes more sense. At no cost to you.
Get My No-Cost Plan Review →