On July 28, 2026, the Centers for Medicare & Medicaid Services set the government’s benchmark for what Part D prescription drug coverage will cost to obtain in 2027, and confirmed that a program which had been softening premium increases since 2025 is going away. The base beneficiary premium for next year will be $41.33, and the temporary subsidy that trimmed premiums for stand-alone drug plans is being shut down at the end of this year. Neither figure is a bill anyone receives directly, but both are the starting math behind what people will actually pay once Medicare’s 2027 plan choices are published in September.
What CMS Actually Set on July 28
The number driving the headline is the base beneficiary premium, a technical figure rather than a bill any individual receives. The national base beneficiary premium for 2027 will be $41.33, calculated from a statutory formula that uses a share of Part D plan bids and estimated reinsurance costs for the standard “basic” benefit. The same July 28 release set the 2027 national average monthly bid amount, the figure CMS uses to calculate the government subsidy paid to plans, at $296.05.
Neither number tells a specific enrollee what their own plan will cost. Per CMS’s 2027 Part D fact sheet, actual plan-by-plan premiums for 2027 won’t be published until the Medicare Advantage and Part D landscape release, expected in mid-to-late September, once insurers finalize their offerings ahead of Open Enrollment.
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How the Number Climbed From $34.70 to $41.33 in Four Years
The base beneficiary premium has now risen every year since 2024, when it stood at $34.70. It moved to $36.78 in 2025, a $2.08 increase, then to $38.99 for 2026. The newly announced $41.33 for 2027 continues that run, an increase of roughly 6% over the 2026 figure.
That trajectory tracks a legal ceiling almost exactly, which is no coincidence.
The 6% Cap Congress Wrote Into the Inflation Reduction Act
CMS’s fact sheets for both 2026 and 2027 cite the same limit: under the Inflation Reduction Act’s premium stabilization provision, the base beneficiary premium cannot increase by more than 6% in any year between 2024 and 2029. Every annual jump since the cap took effect has landed close to that ceiling, this year included.
The cap exists because the IRA rebuilt the Part D benefit structure starting in 2025, eliminating the coverage gap, capping annual out-of-pocket drug spending at $2,000, and shifting more of plans’ costs to an upfront government subsidy instead of back-end reinsurance. CMS anticipated that redesign could push plan bids, and therefore premiums, higher than usual while insurers adjusted, so the law built in a ceiling on how fast the base premium could move during the transition.
The Subsidy That Kept Premiums Lower in 2025 and 2026
The second half of the July 28 announcement is what the headline calls the subsidy that softened it: the voluntary Part D Premium Stabilization Demonstration, first run in 2025. Participating stand-alone drug plans received a uniform $15 reduction applied to the base premium calculation, a $35 cap on how much a plan’s total premium could rise year over year, and narrower risk corridors that limited how much money a plan could lose. Nearly all stand-alone Part D enrollees were covered by a sponsor that opted in.
CMS scaled the demonstration back for its second year rather than keeping it at full strength. For 2026, the uniform premium reduction dropped from $15 to $10, the year-over-year increase limit rose from $35 to $50, and the narrowed risk-corridor protection was eliminated. CMS said at the time it was reducing the amount of premium stabilization from the government “to facilitate the program’s return to operating under regular market conditions.”
Why CMS Is Ending the Demonstration a Year Early
When CMS first designed the demonstration, it described a run of at least three years: one initial year plus “at least two subsequent demonstration years,” with parameters adjusted to reflect market conditions in those later years. That description pointed toward a program running at least through 2027. Instead, the July 28 fact sheet says CMS is discontinuing the demonstration entirely at the end of CY 2026, cutting it off after two years.
CMS’s stated reason is that Part D plan sponsors have had enough time operating under the IRA-redesigned benefit to make reliable bids without extra government support. The fact sheet says CMS’s bid analysis “indicates that Part D plan sponsors had sufficient experience under the redesigned Part D benefit to support their assumptions in developing the prescription drug plan bids,” and that discontinuing the demonstration will return the program to “traditional market conditions” for 2027.
What Households Won’t Know Until September
The base beneficiary premium and the demonstration’s end describe the mechanics behind Part D pricing, not the number a household will actually see on a bill. Actual average premiums have moved differently than the base figure in recent years: CMS’s own data showed the average stand-alone Part D total premium falling from $38.31 in 2025 to a projected $34.50 in 2026, even as the base beneficiary premium rose over the same period, because plan-level bidding and demonstration subsidies don’t move in lockstep with the statutory formula.
Whether that gap holds for 2027 without the demonstration’s cushion won’t be clear until CMS releases the full Medicare Advantage and Part D landscape in mid-to-late September, when actual plan premiums, deductibles, and formularies become public ahead of Open Enrollment, which runs from October 15 to December 7 each year.
This article was produced with AI assistance and reviewed by a human editor. Figures are linked to their primary sources; where a claim could not be verified from the public record, we say so.
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