Creditable coverage is 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 drug coverage. This guide explains what makes coverage creditable, the 63-day rule that triggers the penalty, what counts and what doesn't, 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. 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. 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.
| 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 |
| 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 | 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. 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. 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
For plan year 2026, group health plans have two ways to determine whether their drug coverage is creditable. They may use the existing simplified test, under which coverage is creditable if it's expected to pay at least 60% of participants' drug expenses, or a revised test set at 72%. Which test your plan uses affects whether it lands on the creditable side of the line, so if your employer or retiree coverage is close to the threshold, it's worth confirming its status directly with the plan rather than guessing.
Frequently asked questions
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.
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.
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.
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
- What Is Medicare? Parts A, B, C, and D explained
- How Medicare Part D drug coverage works
- Medicare enrollment periods and the late penalties
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.