Creditable coverage is prescription drug coverage expected to pay, on average, at least as much as Medicare's standard Part D plan. Having it lets you delay signing up for Part D without ever owing a late penalty, which matters because that penalty is permanent: once it attaches, it's added to your premium for as long as you have Medicare drug coverage. This guide explains what makes coverage creditable, the 63-day rule that triggers the penalty, what counts and what doesn't, how to estimate the surcharge, and why you should hold on to the notices your plan sends every year.
What creditable coverage means
When you become eligible for Medicare, you don't have to enroll in a Part D drug plan right away, as long as you have other drug coverage that's at least as good. That's the idea behind creditable coverage. Coverage is creditable when it's expected to pay, on average, at least as much as Medicare's standard Part D benefit.Centers for Medicare & Medicaid Services. (n.d.). Creditable prescription drug coverage. medicare.gov. Retrieved Jul 10, 2026, from https://www.medicare.gov/health-drug-plans/part-d/basics/creditable-coverage If your coverage clears that bar, you can put off Part D for as long as you keep it, and you won't face a penalty when you eventually enroll.
The flip side is just as important. If your drug coverage isn't creditable, or if you have no drug coverage at all, the clock toward a penalty starts running once your Part D enrollment window closes. So the first thing to find out is whether the coverage you already have counts.
The 63-day rule
Here's the rule that decides whether you owe a penalty. The Part D late enrollment penalty applies if you go 63 or more continuous days after the end of your Part D Initial Enrollment Period without either Part D coverage or other creditable drug coverage.Centers for Medicare & Medicaid Services. (n.d.). Creditable prescription drug coverage. medicare.gov. Retrieved Jul 10, 2026, from https://www.medicare.gov/health-drug-plans/part-d/basics/creditable-coverage Stay continuously covered, by creditable coverage or by a Part D plan, and no penalty applies. Let a gap of 63 days or longer open up, and the penalty attaches when you finally enroll.
What counts as creditable coverage
Several common kinds of drug coverage can be creditable. Whether a given plan qualifies is something the plan itself determines and tells you, but these are the categories that typically count.Centers for Medicare & Medicaid Services. (n.d.). Creditable prescription drug coverage. medicare.gov. Retrieved Jul 10, 2026, from https://www.medicare.gov/health-drug-plans/part-d/basics/creditable-coverage
| Coverage type | Can it be creditable? |
|---|---|
| Employer or union group health plan (while you or a spouse work) | Yes, in most cases |
| Retiree coverage from a former employer or union | Yes, in most cases |
| Federal Employees Health Benefits (FEHB) Program | Yes, in most cases |
| COBRA continuation coverage | Only if that specific coverage is creditable |
| TRICARE for military retirees and families | Yes |
| VA drug benefits | Yes |
| Qualified State Pharmaceutical Assistance Program (SPAP) | Yes |
Don't assume, though. The same type of plan can be creditable for one person and not for another, depending on how the specific plan is designed. The plan sponsor is required to tell you which it is.
The annual notice, and why you keep it
Every year, your plan sponsor has to send you a Notice of Creditable Coverage, a written statement telling you whether your drug coverage is creditable.Centers for Medicare & Medicaid Services. (n.d.). Creditable prescription drug coverage. medicare.gov. Retrieved Jul 10, 2026, from https://www.medicare.gov/health-drug-plans/part-d/basics/creditable-coverage It usually arrives before October 15, ahead of Medicare's fall enrollment window, so you can make an informed choice about whether to keep your current coverage or pick up a Part D plan.
Keep these notices. If you later enroll in Part D, you may need to prove that you had continuous creditable coverage, and the notice is your evidence. There's a second deadline to watch as well: when you join a Part D plan, it may send you a letter asking about your prior drug coverage. Respond by the deadline on that letter. If you don't, the plan can charge you the penalty even when you actually had creditable coverage the whole time.
How the penalty is calculated
The penalty is 1% of the national base beneficiary premium for each full month you were eligible for Part D but went without Part D or creditable coverage.Centers for Medicare & Medicaid Services. (n.d.). Avoid late enrollment penalties. medicare.gov. Retrieved Jul 15, 2026, from https://www.medicare.gov/basics/costs/medicare-costs/avoid-penalties That amount is added to your monthly Part D premium, and it stays there for as long as you have Part D. Because the national base premium can change from year to year, the dollar amount of the penalty can shift over time, but the structure is fixed: more months without coverage means a higher permanent surcharge.
That permanence is the whole reason creditable coverage is worth understanding before you decide to delay Part D. A few months of an avoidable gap can mean a small surcharge you carry for the rest of your life.
A 2026 note on how plans test for creditable status
Under the Inflation Reduction Act, Medicare's standard Part D benefit was redesigned for 2026, and CMS updated the actuarial test group health plans use to decide whether their own drug coverage counts as creditable.Centers for Medicare & Medicaid Services. (2026). Final CY 2026 Part D Redesign Program Instructions - CMS. cms.gov. Retrieved Jul 10, 2026, from https://www.cms.gov/files/document/final-cy-2026-part-d-redesign-program-instruction.pdf For plan year 2026, a non-retiree-drug-subsidy group health plan may use either the older simplified determination method or a revised method that CMS set to reflect the richer 2026 benefit (Final CY 2026 Part D Redesign Program Instructions, CMS). Because the revised method raised the bar, some employer or retiree coverage that was creditable in 2024 or 2025 may not clear the line in 2026. If your coverage is anywhere near the threshold, confirm its current status directly with the plan rather than guessing.
Where to get help
If your plan sponsor won't give you a clear answer on whether your drug coverage is creditable, two free sources can help you check before a gap opens up.
Frequently Asked Questions
How do I know if my drug coverage is creditable?
Your plan sponsor is required to tell you in a Notice of Creditable Coverage, usually sent before October 15 each year. If you can't find it, contact the plan's benefits administrator and ask directly whether the drug coverage is creditable. If you still can't get a clear answer, call 1-800-MEDICARE (1-800-633-4227) or your State Health Insurance Assistance Program (SHIP) at shiphelp.org.
Does a short gap in coverage trigger the Part D penalty?
No. The penalty is triggered only by a gap of 63 or more continuous days without Part D or creditable coverage after your Initial Enrollment Period ends. A gap shorter than 63 days does not trigger it.
Is COBRA creditable coverage?
It can be, but not automatically. COBRA continuation coverage counts only if that specific coverage is creditable. Check the Notice of Creditable Coverage for your COBRA plan, and don't rely on COBRA alone to avoid a Part D gap without confirming its status.
How long does the Part D penalty last?
For as long as you have Part D coverage. The penalty is added to your monthly premium permanently, which is why avoiding the 63-day gap in the first place matters so much.
Learn More
Find personalized help confirming your drug coverage is creditable at brevy.com.
The information on Brevy.com is for educational purposes only and is not a substitute for professional legal, financial, or medical advice. Rules vary by state and program and change frequently. Always verify with the relevant agency or a qualified professional. Brevy is not a law firm, financial advisor, or healthcare provider.