- The 2026 penalty is 1% of the $38.99 national base beneficiary premium for each full month you lacked Part D or creditable coverage, rounded to the nearest $0.10.
- It is generally permanent and follows you even if you switch plans.
- You owe no penalty while you have creditable coverage (employer, union, VA, TRICARE) or qualify for Extra Help.
"Do I really have to sign up for Part D if I barely take any prescriptions?" It's a common question — and the answer hinges on a penalty that can follow you for the rest of your life. The Medicare Part D late enrollment penalty is small at first, but it is permanent, so understanding it now can save you money for decades.
What the penalty is
If you go 63 or more consecutive days without Part D or other creditable prescription drug coverage after you first become eligible for Part D, Medicare tacks a surcharge onto your monthly drug plan premium. "Creditable" means coverage that is expected to pay at least as much as standard Part D — for example, an employer or union plan, VA benefits, TRICARE, or federal employee coverage. Your plan must send you a written notice each year (before October 15) saying whether your coverage is creditable. Keep that letter.
Once the penalty applies, you generally pay it for as long as you have Medicare drug coverage — even if you switch Part D plans. It does not expire after a few years.
How the penalty is calculated in 2026
The formula is simple:
1% × the national base beneficiary premium × number of full months without creditable coverage
For 2026, the national base beneficiary premium is $38.99 (this is not your plan's premium — it's a benchmark Medicare sets each year). The result is rounded to the nearest $0.10 and added to your plan's monthly premium. Because the base premium is re-set every year, the dollar amount of your penalty can shift slightly year to year.
Here are a few worked examples using the 2026 base premium:
- 12 uncovered months: 12% × $38.99 = $4.68 → rounded to $4.70/month
- 24 uncovered months: 24% × $38.99 = $9.36 → rounded to $9.40/month
- 36 uncovered months: 36% × $38.99 = $14.04 → rounded to $14.00/month
Medicare's own example: someone with 17 uncovered months pays 17% × $38.99 = $6.63, rounded to $6.60/month on top of their plan premium for 2026.
Who doesn't owe the penalty
Several groups are exempt:
- People with creditable coverage — if you had employer, union, VA, TRICARE, or other creditable drug coverage during the gap months, those months don't count.
- People who qualify for Extra Help (the Low-Income Subsidy) — no penalty while you qualify.
- Short gaps — fewer than 63 consecutive days without coverage doesn't trigger it.
- People in certain special situations — for example, if you had Medicare Advantage drug coverage or were enrolled in some other qualifying arrangement.
If you receive a penalty notice you believe is wrong — for instance, you did have creditable coverage that wasn't counted — you have the right to appeal. The letter from your plan explains how, and includes a form you can use.
How to avoid the penalty entirely
The strategy is straightforward:
- Enroll when first eligible. If you have Medicare and no other drug coverage, join a Part D plan during your Initial Enrollment Period.
- Keep creditable coverage without gaps. If you're still working past 65 and your employer plan counts as creditable, you can delay Part D safely — but get that determination in writing from your benefits administrator each year.
- Enroll promptly when coverage ends. Losing creditable employer coverage gives you a Special Enrollment Period to join Part D — use it before the 63-day clock runs out.
- Check your mail every fall. That creditable coverage notice arrives before October 15. Read it; it decides whether you can safely skip Part D another year.
Does the penalty apply to Medicare Advantage?
Yes. If you enroll in a Medicare Advantage plan that includes drug coverage (MA-PD), the same penalty calculation applies and the surcharge is added to your plan cost. Having an MA-PD plan itself counts as creditable coverage, so it only matters when you went without any creditable drug coverage before joining.
Bottom line: The Part D late enrollment penalty is 1% of the $38.99 2026 base premium per uncovered month — small on its own, but permanent — so enroll when eligible or keep creditable coverage to avoid paying it for life.