If you buy a standalone Medicare Part D prescription drug plan, your premium next year could land anywhere between $10 more a month and a jump as steep as 40 percent, and nobody outside a government office can tell you yet which end of that range you'll hit.
A temporary federal subsidy has kept those premiums from spiking for the past two years, and it disappears at the end of December. Insurers will price their 2027 plans without it, which is why two very different predictions are circulating about what that means for your wallet.
What's actually ending, and why it existed in the first place
The subsidy is called the Part D Premium Stabilization Demonstration. The Centers for Medicare and Medicaid Services (CMS) created it after a redesign of the Part D drug benefit took effect in 2025, adding a hard annual cap on what you pay out of pocket for prescriptions. That redesign shifted more financial risk onto insurance companies, and CMS worried premiums would spike while insurers adjusted to the new rules.
So for 2025, CMS cut $15 off the base premium for participating plans and capped any single plan's year-over-year increase at $35. For 2026, the support shrank to a $10 reduction and a $50 cap. Now it ends completely. CMS says insurers have had two years to find their footing and no longer need the extra help pricing their 2027 plans.
How big could the increase actually be
The high number comes from an estimate that started circulating right after CMS made its announcement, putting the possible increase as high as 40 percent for people in the plans that leaned hardest on the subsidy. CMS disputes it hard. Its own read of the 2027 bids shows that roughly 85 percent of affected beneficiaries will either land on a cheaper plan or see an increase under $10 a month, with every one of them having at least three options priced at $50 or less.
Neither number is confirmed. What is confirmed is what happened the last time this kind of support went away. Before the subsidy existed, CMS's own data showed that people who stayed in their 2024 Part D plan would have seen their monthly premium nearly double on average, with more than a third of them paying at least $40 more a month. That's the scenario the subsidy was built to head off, and it's why both predictions are getting so much attention now that the support is gone.
The one hard figure CMS has released so far is the base beneficiary premium, a statutory benchmark used to calculate individual plan premiums rather than a bill anyone actually receives. For 2027, it's $41.33, up from $38.99, exactly the 6 percent yearly increase the law allows for that specific number. It's a real data point, but it won't tell you what your own plan will actually cost.
Whose bill this actually touches
This change only applies to standalone Part D plans, the kind people buy separately when they have Original Medicare. Enrollment in those plans climbed from 22.8 million people in 2024 to 24.9 million in 2026, partly because the subsidy kept those plans attractive.
If you get drug coverage bundled into a Medicare Advantage plan instead, this subsidy was never yours to begin with. Those plans use rebates to keep their own drug premiums low, and it shows: the average Medicare Advantage drug premium ran about $8 a month in 2026, versus $36 for a standalone plan. If you're on Medicaid or getting Extra Help with your drug costs, you're also insulated. Those programs cover your premium directly, so this fight over base numbers doesn't touch you.
This isn't the same as your Part B premium
It's easy to lump every Medicare cost into one number, but Part B, the part that covers doctor visits and outpatient care, isn't connected to any of this. The latest Medicare Trustees Report projects the standard Part B premium at $209.50 for 2027, up from $202.90, a roughly 3.5 percent increase. That's a modest bump compared with the nearly 10 percent jump between 2025 and 2026, and CMS won't confirm the actual figure until November. If a headline about a 40 percent Medicare spike has you picturing your entire monthly bill, it's worth knowing that number is about drug plan premiums specifically, not your overall Medicare costs.
What's staying the same in 2027
The parts of the drug benefit redesign that actually protect you when you get sick aren't going anywhere. The annual out-of-pocket cap rises to $2,400 in 2027, up from $2,100, and once you hit it, covered drugs cost you nothing for the rest of the year. The standard deductible is rising too, from $615 to $700, but that's a separate number from your premium. Insulin is still capped at $35 a month, and recommended vaccines remain free under every Part D plan. Drug price negotiations continue as well. None of that depended on the subsidy that's ending.
What to do before your plan renews
CMS won't release the real, plan-by-plan 2027 premiums until mid-to-late September. Open enrollment then runs October 15 through December 7, with any changes you make taking effect January 1. That window is your one real chance to shop, and it's worth using even if your current plan feels fine, since plans that got squeezed by the end of the subsidy may raise premiums or trim benefits without much warning. Don't let your coverage auto-renew without checking the numbers first. Pull up the Medicare Plan Finder once the fall landscape posts and compare your current plan against what else is available in your area for the drugs you actually take.
Bottom line
If a big prescription bill lands early in 2027 and blows past what you budgeted, you're not stuck paying it all at once. The Medicare Prescription Payment Plan lets you spread your out-of-pocket drug costs into monthly installments across the rest of the year instead of paying it all at the pharmacy counter. It won't lower what you owe, but it can make a rough month easier to absorb while you wait for the real 2027 numbers to show up in your mailbox.
