How to check whether your drugs are covered
A Medicare Advantage plan with drug coverage only helps with the drugs on its list, at the price its rules set. Here's how to check your own prescriptions against a plan before you commit.
Start with the formulary
Each plan publishes a formulary — the list of drugs it covers. If a drug isn't on the list, the plan generally won't pay for it. So the first question for any plan is simple: is every drug you take on its formulary? A plan with a $0 premium and great extras is the wrong plan if it doesn't cover your prescriptions.
Then the tier and the restrictions
Covered isn't the whole story. Every drug sits on a tier that sets its cost sharing, and a drug can carry rules: prior authorization (prior authorization) means the plan must approve it first; step therapy means you may have to try a cheaper drug before it's covered; a quantity limit caps how much you can get at once. Two plans can both "cover" your drug and charge very different amounts, with very different hoops.
Check it here, across every plan at once
On this site you can search a drug and see, for every plan in your county at the same time, the tier it's on and whether it carries prior authorization, step therapy, or a quantity limit — pulled from the CMS monthly formulary file. Open a county page and use the drug search, or a plan page to check that plan alone.
What the law protects
Some costs are capped regardless of plan. Insulin is limited to $35 for a month's supply. In 2026 your total out-of-pocket for covered Part D drugs is capped at $2,100 for the year — after that you pay nothing more for covered drugs. A handful of drugs under Medicare price negotiation have set prices. These apply across plans, so they're not a reason to pick one over another, but they're worth knowing.
If a drug isn't covered
You still have options: ask the plan for an exception, look at whether a therapeutic alternative on the formulary would work, or compare a plan that does cover it. And if you qualify for Extra Help (the low-income subsidy), your drug costs drop sharply and some plans carry a $0 drug premium — the plan pages here flag which plans qualify at or below the regional benchmark.
Confirm before you enroll
Formularies can change between the filed file and the plan year, and mid-year in limited ways. Before enrolling, confirm each drug with the plan directly or on Medicare.gov, which lets you enter your exact drug list and dosages.