Last year, about 4 million people with a stand-alone Medicare drug plan paid no premium at all. In 2027, according to a KFF analysis published October 2, none of them will have that option unless they qualify for Extra Help. Medicare Part D open enrollment runs from October 15 through December 7, and this is the year when doing nothing has the clearest price tag.
The national average hides what your own plan is doing
CMS’s announcement on September 28 sounded reassuring. The average monthly premium for a stand-alone Part D plan is projected to go from $35.09 to $36, an increase of less than a dollar. Medicare Advantage premiums are projected to fall 16.5%, from $14.37 to $12.
An average across every enrollee says very little about what happens to you if you stay put. KFF looked at that question plan by plan, and the spread is wide. Enrollees who keep Humana Basic Rx will see increases of $6.30 to $30.60 a month, depending on the state. AARP Medicare Rx Preferred, one of the largest plans, is going up by more than $50 a month in all 50 states and DC, by more than $75 in 37 states, and by more than $100 in four. AARP-branded plans cover more than 2 million people who don’t get low-income subsidies.
At the same time, Wellcare Value Script will cost $5.30 a month in 45 states. The cheapest plan and the plan you’re already in may now be very far apart.
Why 2027 premiums moved so much
For 2025 and 2026, CMS ran a premium stabilization demonstration for stand-alone drug plans. KFF notes that it lowered base premiums and capped how much a plan’s premium could rise in a year. In a July 28 notice, CMS confirmed the program ends after 2026. The base beneficiary premium, the starting point for Part D pricing, rises to $41.33 for 2027.
Plans that had been held down by the demonstration are now pricing on their own, which is where the $50-and-up increases come from. The number of plans is shrinking too: KFF counts 316 stand-alone plans for 2027, down from 360, and the average person will have 9 to choose from instead of 11. CVS Health is pulling SilverScript Choice from 13 regions, and Health Care Service Corporation is pulling HealthSpring Extra Rx from 22. If your plan is one of them, you’ll need to pick a new one anyway.
The $2,400 cap changes how you should compare Part D plans
The out-of-pocket cap on covered drugs goes to $2,400 in 2027, up $300 from $2,100 this year. For anyone who takes an expensive brand-name drug, that cap is the most useful number in the whole system, because it puts a ceiling on one half of your annual cost.
Your real yearly cost for a Part D plan is twelve months of premiums plus what you pay at the pharmacy. If you’re a heavy user who will hit the cap in any plan that covers your drugs, the pharmacy half is $2,400 no matter what. The premium becomes the main difference you control.
Here’s how that plays out. A plan at $5.30 a month costs $63.60 a year in premiums, so your maximum total for covered drugs is $2,463.60. If you stay in a plan whose premium went up $75 a month, you’re paying $900 more in premiums than you were last year, and that money buys you nothing extra once you’ve hit the same $2,400 cap. If the increase is $100 a month, the extra cost is $1,200.
For light users who take one or two generics, the math runs the other way: a low premium with a high deductible can cost more than a slightly pricier plan that covers generics before the deductible. That’s why the only comparison that works is one built on your actual drug list.
A cheaper Medicare Advantage premium is a different trade
Some people will look at these numbers and consider dropping their stand-alone plan for Medicare Advantage. CMS says the average drug premium inside Medicare Advantage plans falls from $11.32 to $7 a month after rebates, and it projects 34 million people, about 47.4% of those with Medicare, will be in Medicare Advantage next year. KFF points out that these plans can use federal rebate dollars to lower premiums, which stand-alone drug plans can’t.
That low premium comes bundled with a provider network, prior authorization rules, and a separate out-of-pocket maximum for medical care. For some people it’s a good deal. For someone who travels a lot, sees specialists at an out-of-network hospital, or has a Medigap policy they’d struggle to get back, a $7 drug premium isn’t worth the switch. Treat it as a separate decision, not as a cheaper version of the same plan.
How to run the comparison in an afternoon
Start with your plan’s Annual Notice of Change, which insurers send in the fall. It lists next year’s premium, deductible, and any changes to the drug list. Then go to the Medicare Plan Finder on Medicare.gov, enter your exact prescriptions with dosages, and pick the pharmacies you actually use. The tool shows an estimated yearly cost for each plan that combines premiums and drug costs, and that total is the number to sort by.
Check three things before you switch. First, every drug you take should be on the new plan’s formulary, not only “covered with prior authorization” unless you’re prepared to deal with that. Second, your pharmacy should be preferred in network, since the price difference can be large. Third, if you’re looking at Medicare Advantage, check that your doctors are in the network. KFF found that about 56% of Part D enrollees were in Medicare Advantage drug plans in 2026, and their low premiums come with network rules that a stand-alone plan doesn’t have.
If you’d rather not do it alone, your State Health Insurance Assistance Program offers free, unbiased counseling, and 1-800-MEDICARE answers around the clock. Be careful with agents or brokers who call you. They’re paid by insurers and aren’t required to show you every plan.
Most people skip this, and 2027 is a bad year to
In an older KFF analysis of the 2018 enrollment period, 71% of Medicare beneficiaries said they didn’t compare their coverage options, and 72% of stand-alone drug plan enrollees didn’t either. Inertia is understandable when premiums barely move. It’s expensive when your plan’s premium goes up $900 a year and a plan that covers the same drugs might cost $63.60 for the whole year.
If you’re still a few years from Medicare, this is worth keeping in mind as you plan retirement spending. Health costs don’t stay fixed after 65, and the post on how much to save for retirement by age gives a sense of how big those costs are relative to everything else.
Set aside one afternoon between October 15 and December 7, pull up your Annual Notice of Change, and run your drug list through Plan Finder. Medicare Part D open enrollment is the main yearly window for changing drug plans, and any change takes effect January 1. Your best plan depends on your prescriptions, pharmacies, and health, so a SHIP counselor or a licensed advisor can confirm the details before you enroll.
Sources: CMS, 2027 Medicare Advantage and Part D premiums (September 2026); CMS, 2027 Part D bid and base premium announcement (July 2026); KFF, 2027 stand-alone Part D premiums; Humana, Part D changes for 2027
