Annual Enrollment Guide
How to make the most of AEP (October 15 – December 7).
What AEP is for
The Annual Enrollment Period runs October 15 through December 7 every year. It's the main window to join, switch, or drop a Medicare Advantage plan, and to switch Part D drug plans. Any change you make takes effect January 1.
Read your ANOC in September
Your Annual Notice of Change arrives from your plan every September. It shows what's changing for the coming year — premium, deductible, copays, network changes, formulary changes. Read it. Skimming can cost hundreds of dollars.
Re-check your medications
Plans change formularies annually. A drug that's Tier 2 this year could be Tier 4 next year, or dropped entirely. Run each of your prescriptions through Medicare Plan Finder to see total projected cost per plan.
Confirm your doctors are still in-network
If you're in a Medicare Advantage plan, verify each of your doctors and preferred hospitals are still contracted for the coming plan year. Networks can and do change.
Compare total cost, not just premium
The plan with the lowest premium often isn't the cheapest overall. Add up premium + deductible + expected copays + drug costs to compare fairly. Medicare Plan Finder does this calculation for you.
What AEP is not
AEP is not a Medigap window. Medigap has its own one-time enrollment period at 65 and its own state rules for switching later. AEP also can't be used to sign up for Part B for the first time (that's IEP, SEP, or GEP).