Drug Plan Penalty Base

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Medicare calculates the Part D late-enrollment penalty from a national premium base, not your selected plan’s premium.

Fictional 2026 comparison: assume the plan has confirmed a penalty covering 31 full uncovered months, with no applicable exception. The calculation is 1% × $38.99 × 31 = $12.0869, rounded to the nearest $0.10: $12.10 monthly.

A $45 monthly plan premium becomes $57.10 with that penalty. A $20 alternative becomes $32.10. Switching plans saves $25 in this narrow comparison; it does not erase the penalty. Applying 31% to either plan premium would use the wrong base.

This is not a total prescription budget: deductibles, drug cost sharing and any income-related charge are excluded. Compare actual coverage before changing plans.

A gap of at least 63 consecutive days after the initial enrollment period without Part D or other creditable drug coverage may trigger a penalty. Verify coverage dates and the assessed months with the plan. Extra Help recipients do not pay this penalty. Its dollar amount can change as the national base changes.