Medicare Part D National Base Premium 2024. Copays vary by drug and plan. 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.

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. Cms announced the part d base beneficiary premium for 2025 on july 29, 2024 (this announcement typically occurs at the end of july each year).