Late Enrollment Penalty for Part D
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Late Enrollment Penalty For Part D
Part D Late Enrollment Penalty
The late enrollment penalty is an amount added to your Medicare Part D monthly premium.
You may owe a late enrollment penalty if, for any continuous period of 63 days or more after your Initial Enrollment Period is over, you go without one of these:
A Medicare Prescription Drug Plan (Part D)
A Medicare Advantage Plan (Part C) (like an HMO or PPO)
Another Medicare health plan that offers Medicare prescription drug coverage
Creditable prescription drug coverage
How Much is the Part D Penalty in 2025?
The cost of the late enrollment penalty depends on how long you went without Part D or creditable prescription drug coverage.
Medicare calculates the penalty by multiplying 1% of the “national base beneficiary premium” ($34.70 in 2024) times the number of full, uncovered months you didn’t have Part D or creditable coverage. The monthly premium is rounded to the nearest $.10 and added to your monthly Part D premium.
How do you calculate your premium penalty?
Let’s say you delayed enrollment in Part D for seven months (and you do not meet any of the exceptions listed above). Your monthly premium would be 7% higher for as long as you have Part D (7 months x 1%). The national base beneficiary premium in 2024 is $34.70 a month. Your monthly premium penalty would therefore be $2.43 ($34.70 x 1% = $0.347 x 7 = $2.43) per month, which you would pay in addition to your plan’s premium.
Note: The Part D penalty is always calculated using the national base beneficiary premium. Your penalty will not decrease if you enroll in a Part D plan with a lower premium.
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