Best Medicare Part D Plans 2027: Star Ratings and How to Choose

Reviewed by Russell Noga, Licensed Medicare Insurance Broker (all 50 states) — Last updated October 26, 2026

Every fall, millions of people search for the best Medicare Part D plan. The honest answer is that there isn’t one plan that is best for everyone. This guide shows the official 2027 CMS star ratings for Part D companies, explains why your own medications matter more than any ranking and walks you through how to find the right plan for you.

Before you look at any ranking, know this: the best Part D plan for your neighbor may be the worst plan for you. Every plan has its own list of covered drugs, called a formulary, its own drug tiers, its own pharmacy network and its own premium and deductible.

Two people on the same street can take completely different medications. One may pay almost nothing on a low-premium plan, while the other pays hundreds of dollars more on that same plan because a key brand-name drug sits on a high tier.

CMS rates every Part D contract from 1 to 5 stars each year, based on things like customer service, member complaints, drug pricing accuracy and how well members stay on their medications. Here are the 2027 ratings for the largest national stand-alone Part D companies:

Source: CMS 2027 Star Ratings Data Table, released October 8, 2026. Ratings are by contract. Plans, premiums and availability vary by state and ZIP code.

Some of the best-rated Part D plans are regional. If you live in their service area, they are worth a close look:

Source: CMS 2027 Star Ratings Data Table, released October 8, 2026. Ratings are by contract. Plans, premiums and availability vary by state and ZIP code.

Part D ratings improved for 2027, but top scores are still rare. CMS rated 41 stand-alone Part D contracts:

A plan’s rating can change from year to year, so check it again each fall before you renew.

Say you take three medications, including one brand-name drug. You compare two plans in your area:

Example only, not actual plan quotes. Your costs depend on your drugs, doses, pharmacy and plan.

This is why the plan with the lowest premium is often not the cheapest plan for the year. Medicare’s Plan Finder adds up premium, deductible and drug costs for your exact prescriptions.

Whatever plan you choose, CMS sets the limits. For 2027, plans can charge a deductible of up to $700, up from $615 in 2026. Your out-of-pocket costs for covered drugs are capped at $2,400 for the year, up from $2,100. Once you reach the cap, you pay nothing more for covered drugs until January.

CMS projects the average stand-alone Part D premium at about $36 a month for 2027, and many areas have plans for much less. Covered insulin costs no more than $35 for a month’s supply, with no deductible.

Medicare Supplement plans cover hospital and doctor costs, but not prescriptions. That is why most people with a Medicare Supplement plan also buy a stand-alone Part D plan. Together, they give you broad coverage for doctors, hospitals and drugs.

For the full picture of how drug coverage works, including coverage stages, enrollment periods and the late enrollment penalty, see our guide to Medicare Part D.