How to Switch Medicare Plans During Open Enrollment

Switching Medicare plans during open enrollment — the Annual Enrollment Period (AEP) from October 15 to December 7 — is simpler than most people think. But it requires knowing the right steps, the right deadlines, and the right things to check before you commit to a new plan.

When Can You Switch Medicare Plans?

You can switch Medicare plans during these official enrollment windows:

• Annual Enrollment Period (AEP): Oct 15 – Dec 7 — any Medicare plan
• Medicare Advantage Open Enrollment Period (OEP): Jan 1 – Mar 31 — switch MA plans or return to Original Medicare (once)
• Special Enrollment Period (SEP): Triggered by qualifying events like losing employer coverage, moving, or plan exit
• 5-Star SEP: Dec 8 – Nov 30 — switch to a 5-star plan once per year

AEP is your primary switching window — the only time you can make any change without a qualifying life event.

What Plans Can You Switch Between?

Original Medicare → Medicare Advantage

You can switch during AEP. Your Medigap plan won’t cancel automatically — you must cancel it separately once your MA plan starts January 1. Important: if you later want to return to Medigap, most states allow medical underwriting outside your Medigap Open Enrollment Period.

Medicare Advantage → Original Medicare

Drop your MA plan and return to Original Medicare during AEP. Coverage begins January 1. Adding Medigap afterward is complicated — talk to a broker before making this switch.

Medicare Advantage → Different Medicare Advantage Plan

The most common switch. Simply enroll in a new MA plan — new enrollment automatically cancels your old plan. Nothing else required.

Part D → Different Part D Plan

New Part D enrollment automatically cancels old coverage. New plan starts January 1, old plan ends December 31.

Step-by-Step: How to Switch Medicare Plans

Step 1: Read Your Annual Notice of Change

Mailed every September. Outlines all changes coming to your plan for next year. Read it before October 15 so you know what’s changing before AEP begins.

Step 2: Know Your Non-Negotiables

Before comparing plans: Which doctors must be in-network? What medications do you take? What’s your monthly premium budget? Do you need dental, vision, or hearing coverage?

Step 3: Use the Medicare Plan Finder

Go to medicare.gov/plan-compare. Enter ZIP code, medications, and preferred doctors. Sort results by “Estimated Annual Drug and Premium Costs” — not premium alone. The Plan Finder shows all available plans with calculated total annual costs.

Step 4: Compare Your Top 2-3 Plans

For finalist plans, download the Summary of Benefits. Compare: star rating, MOOP, drug tiers, copays, and supplemental benefits (dental/vision/OTC).

Step 5: Verify Doctor Networks Directly

Call your doctor’s office: “Do you accept [Plan Name] for 2027?” Don’t trust online directories alone — they can be outdated. This 5-minute call can save thousands in out-of-network costs.

Step 6: Enroll in Your New Plan

Enroll at medicare.gov, the plan’s website, by calling 1-800-MEDICARE, or through a licensed broker. Old coverage ends December 31; new coverage begins January 1.

Step 7: Cancel Plans That Won’t Auto-Cancel

Medicare Advantage: new enrollment auto-cancels old plan. Part D: same. Medigap does NOT auto-cancel — you must call the insurance company directly to cancel it.

Important Rules About Switching

You can switch multiple times during AEP. The last enrollment before December 7 is what takes effect.

Doctor access doesn’t transfer. If switching from Original Medicare to MA, your doctors must be in-network in the new plan. Check before you switch.

Medigap has underwriting rules. In most states, Medigap companies can apply medical underwriting outside specific enrollment periods. Health conditions can affect eligibility and pricing.

After You Switch: Timeline

• December-January: Receive new insurance card in the mail
• January 1: New coverage begins, old coverage ends
• January-February: Update new plan ID with all providers you visit
• January-March 31: MA OEP begins if you change your mind