Medicare Part D Tiers, Copays and Coinsurance Explained
Medicare drug plans commonly divide covered medications into tiers, with lower-tier drugs generally costing less and higher-tier drugs generally costing more.
Creditable Prescription Drug Coverage Explained
Last Modified: 10/02/2026 | Reviewed by Keith Armbrecht (NPN 634015)
Quick Summary
Creditable prescription drug coverage is drug coverage that’s expected to pay, on average, at least as much as Medicare’s standard Part D prescription drug coverage.
If you have other creditable prescription coverage, you may be able to delay enrolling in Part D without a late enrollment penalty.
The key is to avoid going:
63 consecutive days or more
without Medicare drug coverage or another source of creditable prescription coverage after you’re eligible.
Key Facts
- Creditable coverage can allow you to delay Part D.
- Not all employer drug coverage is automatically creditable.
- Your insurer or employer should tell you whether coverage is creditable.
- Keep all creditable-coverage notices.
- The 63-day rule is important.
- Losing creditable coverage can trigger a Special Enrollment Period.
- Going too long without coverage can create a Part D penalty.
- VA coverage is generally considered creditable.
- TRICARE prescription coverage is generally considered creditable.
- Employer and retiree coverage must be evaluated individually.
What Does “Creditable” Mean?
It means the prescription coverage is actuarially expected to provide coverage that’s at least as good as Medicare’s defined standard drug benefit under Medicare’s rules.
Your employer or plan administrator generally provides a notice telling you whether the coverage qualifies.
Why Does It Matter?
Suppose you’re 65 and still working.
Your employer plan includes prescription coverage.
If that coverage is:
Creditable
you may generally delay Part D without accumulating a penalty.
Later, when your employer coverage ends, you can enroll in Medicare drug coverage.
Keep the Notice
Don’t throw away your:
Notice of Creditable Coverage
You may need it later to prove you maintained qualifying drug coverage.
The 63-Day Rule
If you go:
63 consecutive days or more
after the end of your Medicare drug enrollment opportunity without:
Part D
or:
Other creditable prescription coverage
you may face a late enrollment penalty.
What If You Lose Creditable Coverage?
Losing qualifying drug coverage generally provides an opportunity to enroll in Medicare drug coverage.
Don’t wait several months after employer insurance ends before investigating Part D.
Employer Coverage
Ask the benefits department:
“Is my prescription drug coverage creditable for Medicare Part D?”
Don’t simply ask:
“Do I have drug coverage?”
Those are two different questions.
Video Explanation from Keith
Is Your Employer Drug Coverage Good Enough for Medicare?
Keith's Take
The word to remember is:
Creditable.
If you’re working after 65 and someone tells you:
“You have drug coverage through work.”
My next question is:
“Is it creditable for Medicare Part D?”
Get the answer in writing and keep the notice.
That little document can become very important if Medicare later asks why you delayed Part D.
Keith Armbrecht
Medicare on Video
Frequently Asked Questions
Q. What is creditable coverage?
A. Drug coverage expected to pay at least as much as Medicare's standard drug coverage under Medicare rules.
Q. Can employer coverage be creditable?
A. Yes.
Q. Is all employer coverage creditable?
A. Not necessarily.
Q. How do I know?
A. Your employer or insurance plan should provide a creditable-coverage notice.
Q. Should I save the notice?
A. Yes.
Q. How long can I go without creditable drug coverage?
A. Avoid 63 consecutive days or more.
Q. Can losing creditable coverage let me join Part D?
A. Yes, qualifying loss generally creates an enrollment opportunity.
Q. What happens if I wait too long?
A. You may face a Part D late enrollment penalty.
Official Government Sources
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