Part D coverage varies by plan, but CMS rates plans yearly based on various criteria. Review the available Part D plans in your area and compare them with your health needs to make the best choice.

Finding the best Medicare coverage for your needs is a complicated process involving many choices. Select a Medicare Part D plan if you add prescription drug coverage.

Read on to find out about the best-rated Part D plans for 2025 and how to select the best Part D plan for you.

Part D plans can be particularly confusing because there are no federal plans, only those offered by private insurance providers. These plans can vary widely regarding coverage and costs, and what plan might work best differs for each person.

That said, the Centers for Medicare & Medicaid Services (CMS) publishes ratings for Part D plans every year. For 2025, CMS awarded two companies providing stand-alone Part D plans with five stars, the highest possible rating. These are Upmc Health Benefits, Inc. and The Independent Health Benefits Corporation.

In addition, it has awarded seven Medicare Advantage plans that include prescription drug coverage with the same rating. These are:

  • Highmark Choice Company
  • Leon Health, Inc.
  • Network Health Insurance Corporation
  • Alignment Health Plan of North Carolina, Inc.
  • Healthsun Health Plans, Inc.
  • Mcs Advantage, Inc.
  • Optimum Healthcare, Inc.

The criteria that CMS uses to determine its ratings for Part D plans include:

  • lower number of member complaints about the plan
  • improvements in the quality of covered drugs
  • ease of access to needed drugs through the plan
  • your ability to stick to your drug treatment regimen under your plan for conditions like diabetes or high blood pressure
  • whether the plan’s call center provides interpreter services
  • the accuracy of your listed drug prices under the plan
  • the overall rating of the drug plan

It’s important to remember, however, that not all stand-alone Part plans or Part C plans with drug coverage are available in your region. You can check what’s available in your zip code on Medicare.gov.

You can sign up for a Medicare Part D plan as soon as you become eligible for Medicare. Even if you don’t need many medications at that time, you may want to sign up for a Part D prescription plan right away.

Aside from special circumstances, you’ll have to pay a late enrollment penalty if you sign up for a Part D plan after being first eligible.

To start the process of finding a Part D plan, you may first want to decide if you’re going to stick with original Medicare (Part A and Part B) or if you’re going to choose Medicare Advantage (Part C).

Some Medicare Advantage plans combine parts A and B with optional extra coverage for things like prescriptions.

You can use the following steps to shop for a Part D plan.

To enroll in a Part D plan for the first time, begin researching your needs and options before you turn age 65. You’ll have 3 months before and 3 months after your 65th birthday month to sign up for Medicare plans, including Part D plans.

After initial enrollment in original Medicare (parts A and B), you have 63 days to choose a Medicare Advantage and/or a prescription drug plan. If you don’t enroll now, you’ll have to wait for specific enrollment periods.

To enroll in a Part D plan, you have several options. You can enroll:

  • online through the Medicare plan finder tool
  • by calling Medicare directly at 800-MEDICARE (800-633-4227)
  • by contacting a private insurance company that offers the Part D plan you want or visiting the company’s website to submit an application

When you enroll, be prepared to provide some basic information about yourself. You’ll also need to have your Medicare card ready to give your Medicare number and the date your original Medicare coverage began.

Medicare Part D is a private insurance plan that the federal government backs.

While there are no federal programs for prescription coverage, Medicare does set a standard for what private plans must cover. Each prescription drug plan must offer at least two medications in the most commonly prescribed categories and most drugs within the six protected classes.

But each plan can still create its own list of covered drugs as long as there are two in each medication category. These lists are called formularies, and it’s possible that some drugs you need may not be included.

Even for covered medications, the cost can vary from plan to plan because there are different medication levels within the formulary. These levels—called tiers—are based on your plan’s preference for certain generic, brand-name, or specialty medications. The tier your medication falls on will determine the cost you’ll pay.

Every Part D plan has a different premium. That said, CMS estimated the average overall monthly cost of Part D coverage to be around $46.50 in 2025.

Your Part D benefits are separate from pharmacy price trackers like GoodRx. Usually, you either have to use your Part D benefits when getting medication from the pharmacy, or you use a discount provided by GoodRx. In most cases, you can’t combine these benefits.

Every year, CMS publishes a list of ratings for Part D and C plans. You can search Medicare.gov to see if these plans are available in your area.

That said, there are many things to consider when making coverage choices during your initial enrollment in Medicare.

Consider your current and future needs, as well as your budget, when researching prescription drug plans. Enrolling late could cost you a lifelong penalty.

There are also several programs and organizations that can help you choose a plan and afford coverage for your medications.