Staying Fit
The Centers for Medicare & Medicaid Services (CMS) assesses Part D prescription drug plans and Medicare Advantage plans every year based on several quality measures. CMS gives each plan a star rating from five stars (excellent) to one star (poor).
Based on a lot of data. To create the ratings Medicare looks at surveys of people enrolled in the plans, complaints filed against plans, Medicare investigators’ spot-checks, reliability of pricing information and other factors. The plans receive an overall star rating plus separate star ratings in myriad categories:
- Part D prescription plans are rated on up to 12 quality measures, such as customer service and member experience.
- Medicare Advantage plans with drug coverage are rated on those 12 categories and up to 28 additional performance measures, such as the percentage of eligible participants who get certain health screenings and how well the plan cares for people with certain chronic conditions.
- Medicare Advantage plans without drug coverage are rated only on those 28 performance measures.

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Why look up a plan’s star ratings? If you want to know how one plan stacks up against another in customer service or managing care for a chronic condition you may have, star ratings are a good source. You can look up a plan’s rating in each category, in addition to its overall star ratings, when using the Medicare Plan Finder to compare Part D or Medicare Advantage plans available in your area.
What do Medicare star ratings measure?
Medicare Advantage plans’ star ratings are based on five major categories:
2023 Medicare star ratings
The percentage of plans in each star category
Medicare Advantage | Part D | |
5 stars | 11.2% | 3.9% |
4.5 stars | 13.2% | 13.5% |
4 stars | 26.8% | 13.5% |
3.5 stars | 22.9% | 21.3% |
3 stars | 17.8% | 30.8% |
2.5 stars | 7.3% | 7.7% |
2 stars | 0.8% | 7.7% |
1.5 stars | 0.0% | 1.9% |
Numbers may not total 100% because of rounding.
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