Medicare Part D is prescription drug coverage. Before comparing plans or delaying enrollment, identify what prescription coverage you have now and whether it is creditable. A medical insurance card, a pharmacy discount card and a creditable-coverage notice answer different questions.
What does creditable coverage mean?
Creditable prescription coverage is expected to pay, on average, at least as much as Medicare drug coverage. Your current plan must tell you whether its drug coverage is creditable. Keep the applicable annual notice and the dates that coverage applied; do not infer status from the plan's name or from how little you use medication.
Going 63 days or more without Medicare drug coverage or other creditable drug coverage after eligibility can lead to a Part D late-enrollment penalty when enrolling later. A drug-plan request for proof has its own response deadline. Discount cards and samples are not prescription insurance.
Compare coverage and costs with the same information
Part D premiums and drug costs vary by plan. The drugs covered and the pharmacy used affect costs. Use current plan information for the year being compared and ask the plan about any approval, quantity or exception requirements that apply to a particular prescription. A past receipt does not establish next year's coverage.
| Record or question | Who can confirm it? |
|---|---|
| Current creditable-coverage notice | Your current coverage administrator |
| Coverage start and end dates | The old and new plans |
| Current drug and pharmacy information | The plan and pharmacy using your private list |
| Unresolved coverage condition | The plan, with your prescriber where needed |
| Effect on family or retiree benefits | Your employer, union or retirement-plan administrator |
Use your medication list privately with the official plan-comparison process. Do not enter prescriptions, diagnoses or Medicare numbers into a general website inquiry. If two estimates differ, ask which plan year, pharmacy or coverage assumption caused the difference.
Check other benefits before enrolling
Joining Medicare drug coverage can affect employer or retiree coverage for you or your family. Confirm the consequences before a change. Federal and postal households should also use the existing FEHB comparison and PSHB Medicare questions.
Your next step is to obtain the current notice and resolve remaining questions with the administrator or plan. If costs are difficult to manage, review Medicare Savings Programs and Extra Help. This guide does not select a drug plan or determine a penalty.
Browse federal benefits, retirement and insurance topics or read how we prepare and check our guides.
Sources
- Medicare: Creditable prescription drug coverage, checked November 4, 2026
- Medicare: What does Medicare cost?, checked November 4, 2026
- Medicare: Retiree insurance and Medicare, checked November 4, 2026
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