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Plain-language Medicare guidance • Enrollment windows • Clear decisions.

Medicare Annual Enrollment is open now October 15 – December 7 · 33 days left
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Medicare • Retirement Guidance
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Prescription Drug Coverage (Part D)

Drug coverage comes from a private plan. A gap without creditable drug coverage can lead to a late-enrollment penalty.

How Part D works

Part D plans are sold by private insurers, either standalone (alongside Original Medicare or Medigap) or built into a Medicare Advantage plan. Each plan has its own formulary — the list of covered drugs and their tiers — which is why the same prescription can cost very different amounts on different plans.

Federal law now caps what you pay out of pocket for covered drugs each year (the cap is indexed annually), which has made the annual plan comparison simpler — but the formulary match still decides most of what you actually pay.

When a late-enrollment penalty can apply

After your Initial Enrollment Period, going 63 consecutive days or more without Part D or other creditable drug coverage can trigger a penalty. It is calculated as 1% of the national base beneficiary premium for each full uncovered month, and generally applies for as long as you have Part D. People who get Extra Help do not pay this penalty. Check whether your existing coverage is creditable before changing it, even if you take no medications.

Educational information, not advice about any specific plan. For details on every option available in your area, visit Medicare.gov or call 1‑800‑MEDICARE.