Medicare Part D for 2027: How to Check Your Prescriptions Are Still Covered

Walt takes four prescriptions, and one of them, a brand-name drug, is the reason he stays on a particular Part D plan. In late September, an envelope from the plan arrives. He recognizes the logo, assumes it is the usual mail, and sets it aside. Three months later he stands at the pharmacy counter in January and learns the plan now puts that drug behind a prior authorization, at a higher tier. Walt is an invented example, but the mistake is real and common, because Medicare coverage renews automatically unless you change it. Open Enrollment runs October 15 through December 7, and that is the window to catch the problem before it costs money.

This guide walks through what to check for 2027, in the order that finds problems fastest. It also covers what is already known about next year's Part D numbers from CMS, what is still unknown, and what to do if a drug you rely on is no longer covered as before. Plan-specific details, like your exact copayments, can only come from your own plan documents, so treat this as a method, not a verdict on any plan.

Start with the envelope you set aside

Every Medicare plan sends an Annual Notice of Change, usually called the ANOC, each fall. Medicare.gov says plans send it in September, and it lists changes to coverage and costs that take effect in January. If you did not get one, contact your plan. The notice is the fastest way to learn whether your plan is keeping your drugs, moving them to a different tier, or adding rules.

Read three things first: your drug list (formulary) changes, your pharmacy network changes, and your premium and deductible. Compare the new numbers with what you paid this year, not with what you remember paying. Then keep the notice next to your list of prescriptions, because you will need both for the next step.

What is already known about 2027 Part D

Some national numbers for 2027 are official. In its April 2026 final announcement, CMS set the 2027 defined standard Part D deductible at $700, up from $615 in 2026. It set the annual out-of-pocket threshold at $2,400, up from $2,100 in 2026. Medicare.gov's own fact sheet repeats the $2,400 figure as the 2027 cap on out-of-pocket costs for covered drugs. Once your out-of-pocket costs for covered drugs reach that cap, you pay nothing more for covered Part D drugs for the rest of the calendar year.

Here is how the standard benefit works with those numbers, using an illustrative drug year. You pay the first $700 yourself. After that, you pay 25 percent of each drug's cost until your out-of-pocket total reaches $2,400. To get from $700 to $2,400, you need to pay $1,700 in coinsurance, which at 25 percent corresponds to $6,800 of drug costs after the deductible. Anything beyond that point costs you nothing. Real plans vary, because many use copayments and different tiers instead of the textbook structure, and a plan's own deductible may differ from the standard one. Treat this as the outline of the protection, and check your plan's own numbers.

CMS also announced on July 28, 2026 that the national base beneficiary premium for 2027 is $41.33. That is a benchmark used in plan pricing, not the premium you will pay, and individual plan premiums differ. CMS also said it will end the Part D Premium Stabilization Demonstration after 2026. How that affects premiums for the plan you hold is something only your own ANOC or the Plan Finder can tell you.

Reading a formulary without getting lost

Every Part D plan has a formulary, which is its list of covered drugs. Medicare.gov explains that plans often sort drugs into tiers, and that a lower tier generally costs less than a higher one. A typical plan might have a lowest tier for most generics, a middle tier for preferred brands, a higher tier for non-preferred brands, and a specialty tier at the top, though each plan can arrange its tiers differently.

Next, look for the rules attached to each drug. Medicare.gov lists three that matter most. Prior authorization means you and your prescriber must get the plan's approval before it covers the drug. Step therapy means you must first try a less expensive drug on the list. Quantity limits cap how much of a drug the plan covers in a period, such as 30 tablets a month.

Medicare.gov also notes that plans can change their drug lists during the year and must tell you about changes that affect drugs you take. A drug that is covered on January 1 is therefore not guaranteed all year, which is another reason to look again at your coverage every fall.

There is one new factor for 2027. Medicare.gov says prices Medicare negotiated for the next 15 Part D drugs take effect on January 1, 2027. If one of your medications is on that list, ask your plan how the negotiated price affects your cost sharing.

Which part of Medicare pays for the drug

Part D does not cover every drug you might receive. Medicare.gov explains that Part B covers a limited number of outpatient drugs, usually those you would not typically give to yourself, such as drugs given at a doctor's office or in a hospital outpatient setting. Part D covers drugs that Part B does not. If a medicine is given by injection in a clinic, the cost may fall under Part B rules, not your drug plan's formulary, so ask the office which one applies.

Vaccines follow their own rules. Medicare.gov says drug plans must cover all commercially available vaccines when medically necessary, and that you pay nothing out of pocket for Part D adult vaccines recommended by the Advisory Committee on Immunization Practices.

If your drug coverage comes bundled in a Medicare Advantage plan, the same review applies, with one more layer. You also need to check that your doctors and hospitals are in the plan's network. Medicare also gives people in Medicare Advantage Plans a second chance from January 1 to March 31 to switch to a different Medicare Advantage Plan or to Original Medicare with a separate drug plan, but waiting means a few months of costs you could have avoided.

Check the pharmacy as carefully as the drug

A drug can be covered and still cost more at the wrong pharmacy. Medicare.gov explains that plans contract with in-network pharmacies, and in some plans your drugs are only covered if you fill them there. Some plans also have preferred in-network pharmacies, where your copayment or coinsurance may be lower.

Mail order is worth a look if you take medicines regularly. Medicare.gov says some plans offer mail-order programs that deliver up to a 3-month supply, sometimes with automatic refills. If you use an out-of-network pharmacy, you will probably pay full cost, and any refund from the plan covers only part of the bill. If your plan changed its network this year, your favorite pharmacy may no longer be the cheapest one, or even in the network.

Run the comparison the right way

Medicare's Plan Finder, at Medicare.gov/plan-compare, can show 2027 plans now. Medicare says you can use it to compare plans side by side, get estimates of your total out-of-pocket costs, and see customized information for your preferred pharmacies and drugs. Log in, or enter your drugs one at a time, with the correct dose and quantity.

Three habits make the results more reliable. List every prescription, including generics and drugs you take only occasionally. Select your actual pharmacy, not the default one. And compare the estimated total cost, not only the monthly premium. A plan with a low premium and a high price on your specific drug can cost more over the year than a pricier plan that covers it well.

Then check the plan's rules for each drug against the Plan Finder results. If a drug carries prior authorization, ask your prescriber's office whether they can start the paperwork before January. The Plan Finder estimate is a guide, and your plan's formulary and the final cost figures control.

If your drug is not covered the way you need

Medicare.gov describes several safety nets. When your drug coverage begins, you may get a transition fill, a one-time 30-day supply of a drug you have been taking that your new plan does not cover or that requires prior authorization or step therapy. A transition fill is a bridge, not a solution, so use it to start the next step.

That step is usually an exception request. You or your prescriber can ask the plan to cover a drug that is not on its list, waive a rule such as step therapy or a quantity limit, or charge a lower amount for a drug in a higher tier. Your prescriber must provide a supporting statement explaining why the drug is medically necessary or why alternatives would be less effective or cause adverse effects. Medicare.gov also notes that starting January 1, 2027, your plan may be able to process prior authorization requests electronically.

If you are still choosing a plan, the clean fix is to switch to one that covers your drug on better terms, rather than hoping for an exception later.

Spreading out the cost

The Medicare Prescription Payment Plan lets you pay covered drug costs in monthly bills rather than at the pharmacy. According to Medicare's fact sheet, all plans offer it, it is voluntary, and it costs nothing to join. It does not save you money or lower your drug costs. Each month your bill is based on what you would have paid, plus last month's balance, divided by the number of months left in the year.

Medicare's example shows how it works. Someone with $600 a month in out-of-pocket drug costs who joins in January 2027 pays $200 the first month, which is the $2,400 cap divided by 12 months, and the remaining $400 is carried forward. Payments change from month to month, and by the end of the year you never pay more than you would have paid at the pharmacy, or more than the $2,400 cap.

Medicare says the plan may not suit you if your drug costs are low, steady each month, or if you sign up late in the year. If you pay a plan premium, that is billed separately, and you should pay it first so you do not lose coverage.

Help for people with limited income

Extra Help is a Medicare program that helps people with limited income and resources pay for Part D premiums, deductibles, and copayments. You can apply through the Social Security Administration at any time, before or after you enroll in Part D. Medicare Savings Programs and state pharmaceutical assistance programs may also help. Because eligibility depends on income and resources, ask Social Security or your State Health Insurance Assistance Program, known as SHIP, to review your situation. Many people qualify and do not know it, according to Medicare.

A short plan for the next seven weeks

Before December 7, read your ANOC and make a list of your prescriptions. Run the Plan Finder with your real pharmacies, and call your doctor's office about any prior authorization. Enroll in a new plan by the deadline if the numbers favor it. The plan must receive your enrollment form by December 7.

Free counseling is available. You can call 1-800-MEDICARE, which is staffed around the clock, or your local SHIP.

Walt's lesson is simple. The envelope you ignore may hold the one change that matters most to your prescriptions, so open it this week.