CMS Sets 2027 Part D Base Beneficiary Premium at $41.33 a Month, Rising 6% to the Legal Cap
The national base beneficiary premium for Medicare Part D will be $41.33 a month in 2027, up $2.34 from $38.99 in 2026, a rise of 6 percent, according to bid information released by the Centers for Medicare & Medicaid Services (CMS) on July 28, 2026. The figure is the starting point from which each drug plan's own premium is calculated.
The base beneficiary premium is not a bill anyone actually pays. It is a single national reference figure: each Part D plan adjusts it according to its own bid and benefit design, so monthly premiums differ from plan to plan in the same year. What an individual pays depends on the plan they choose.
The $41.33 figure is where it is because a legal cap bound it. By statute, the premium is the lower of two calculations. The first takes the prior year's base premium and multiplies it by 1.06: $38.99 times 1.06 equals $41.33. The second applies the beneficiary premium percentage to the national average bid and produced $94.06. The lower result governs. Under the Inflation Reduction Act's premium stabilization provision, growth in the base premium is capped at 6 percent a year from 2024 through 2029, and 2027 lands exactly on that ceiling.
The same release set two related figures. The Part D national average monthly bid amount for 2027 is $296.05, up from $239.27 in 2026. The bid amount is the enrollment-weighted average of what plans bid to provide basic drug benefits, and it is used mainly to calculate the federal subsidy paid to plans. The de minimis amount relevant to low-income premium subsidies is $2.
Open enrollment for 2027 coverage runs from October 15 to December 7, 2026, and choices take effect on January 1, 2027. Beneficiaries with a drug plan can use that window to compare their plan's annual notice of change against premiums, deductibles and whether their regular medications remain on the formulary, before deciding to stay or switch.
(Source: Centers for Medicare & Medicaid Services)
Source: Centers for Medicare & Medicaid Services
Published by GSM · USA (original Chinese edition)
Photo: 图片来源：Wikimedia Commons「52nd MDG Pharmacy (7580222)」（美国空军照片，公共领域），图中为药房工作人员清点处方药胶囊 Image: Wikimedia Commons, "52nd MDG Pharmacy (7580222)" (U.S. Air Force photo, public domain), showing prescription capsules being counted at a pharmacy
