Medicare Part D helps cover the cost of prescription drugs, but not all plans are the same. Private insurance companies (not Medicare itself) offer Part D plans, and each company creates its list of covered drugs, known as a formulary. That means one plan might cover your medications at a lower cost, or not at all, than another plan.
Well-known insurance companies that offer Part D plans include:
- Aetna
- UnitedHealthcare (AARP)
- Humana
- WellCare
- Cigna
Each plan varies in:
- Which drugs are covered
- What you’ll pay (copays, coinsurance, deductibles)
- Preferred pharmacy networks
That’s why it’s important to review your plan every year, especially if your prescriptions have changed. Your broker should help with this review annually during the Annual Enrollment Period (AEP).
When Can You Change Your Part D Plan?
You don’t have to stay locked into one plan forever. You can make changes during these key windows:
- Annual Enrollment Period (AEP): Oct 15 – Dec 7
Switch to a new Part D plan or Medicare Advantage plan. New coverage starts Jan 1. - Open Enrollment Period (OEP): Jan 1 – Mar 31
If you’re on a Medicare Advantage plan, you can switch to a different one or return to Original Medicare with a standalone Part D plan.
You may also qualify for a Special Enrollment Period (SEP) if you lose coverage, move, or have other qualifying life changes.
Pro Tip: Even if you’re happy with your plan, it might not be your best option next year. Formularies, premiums, and pharmacy networks change annually, and so does your health.