The Part D Late Enrollment Penalty: How It Accrues and Sticks Forever

Skip creditable drug coverage for 63+ consecutive days after you become Medicare-eligible and a lifetime late enrollment penalty attaches to your future Part D premiums: 1% of the national base beneficiary premium for every uncovered month, rounded up, paid every month for as long as you have Part D.

Element	Rule	Example
Break in creditable coverage	63+ consecutive days	A 7-month gap accrues 7%
Penalty size	1% of national base premium per month	2025 base ≈ $36.78 → ≈ $0.37/month per month uncovered
Example penalty	12 uncovered months	≈ $4.41 added to every monthly premium, forever
When it applies	When you finally enroll in Part D	Added to whatever plan you choose
Escape routes	Very few — exception appeals for credible-coverage proof	Employer-plan documentation is the common defense

Why “I take no drugs now” is not a defense

The penalty is designed to keep people enrolled while healthy so risk pools stay balanced. CMS does not care that you filled nothing — only that you lacked creditable coverage for 63+ days. The monthly amounts look trivial ($5–15 for most real-world cases) but they compound forever and rise with the base premium, and they can attach simultaneously to late Part B enrollment penalties, which are far larger (10% of the Part B premium per full year late).

The cheap insurance move

If you take no medications at 65, enroll in the cheapest credible Part D plan in your county anyway — often $7–15/month. It keeps the clock from starting and doubles as catastrophic drug protection ($2,000 cap) against a new expensive diagnosis. Declining coverage to save $100 a year risks a permanent surcharge plus the far bigger Part B trap if you also skip that.

FAQ

Is the Part D penalty charged monthly or yearly?

Monthly — it is added to your Part D premium every month for life once triggered.

Does VA or Tricare count as creditable coverage?

Yes — VA, Tricare, most employer plans and COBRA count. Keep the creditable-coverage letter; it is your proof if CMS miscalculates.

Can I appeal the penalty?

Yes — if you can show creditable coverage during the alleged gap or CMS miscounted the days, an appeal usually succeeds.

Related reading: Part D mechanics · IRMAA surcharge · Medigap OEP · Medicare FAQs