Understanding Medicare Part D Star Ratings: A Benchmark for Quality
The Medicare Part D Star Ratings system is designed to measure the quality of prescription drug services provided to consumers enrolled in stand-alone Prescription Drug Plans (PDPs) or Medicare Advantage Prescription Drug (MA-PD) plans. CMS evaluates these plans across various measures of quality and performance, assigning them a rating from 1 to 5 stars, with 5 stars representing the highest level of quality. This system allows individuals to easily compare medicare part d drug plans and identify those that consistently deliver high-quality care and services. By focusing on objective data, the Star Ratings system promotes transparency and encourages plans to continuously improve their performance to better serve their enrollees.
Key Highlights from the 2025 Star Ratings for Part D Plans
The 2025 Star Ratings reveal important trends in the performance of Medicare Part D plans. For stand-alone PDPs, approximately 27% of plans (11 contracts) achieved four or more stars for their 2025 Part D Rating. However, when weighted by enrollment, only about 5% of PDP enrollees are currently in contracts that will have four or more stars in 2025. This indicates that while some high-quality plans exist, a significant portion of enrollees are in plans with average or below-average ratings.
Changes in Star Ratings from year to year are expected and reflect the dynamic nature of plan performance and the evolving benchmarks set by CMS. For 2025, many measure-level cut points increased, meaning plans had to achieve higher performance to maintain or improve their Star Ratings. These shifts are driven by factors such as the removal of extreme outliers in performance data, the return to pre-pandemic performance levels in some measures, and an overall increase in the performance of many contracts. These changes underscore the importance of reviewing the latest Star Ratings each year to compare medicare part d drug plans effectively.
Minor Methodological Adjustments for 2025 Star Ratings
While there were no major methodological overhauls for the 2025 Star Ratings, CMS implemented minor adjustments to refine the accuracy and stability of the system. One notable change is the application of bi-directional guardrails to the Part D Medicare Plan Finder measure, starting with the 2025 ratings. These guardrails are activated if cut points change by more than 5% after mean resampling, ensuring smoother transitions and preventing drastic fluctuations in ratings from year to year. For the 2025 Star Ratings, guardrails were not applied to this specific measure as cut points did not shift beyond the 5% threshold.
Building on previous updates, the 2025 ratings also reflect the impact of Tukey outlier deletion, a methodology introduced in the 2024 Star Ratings. This statistical technique removes extreme outliers from performance data when setting cut points for non-CAHPS measures. By eliminating the influence of these extreme values, particularly those at the lower end of performance, Tukey outlier deletion leads to more accurate and stable cut points that better reflect overall plan performance. This refinement contributes to a more reliable system for consumers to compare medicare part d drug plans.
Rating Distribution for Part D Plans: 2022-2025 Trends
Analyzing the distribution of Part D ratings over the past four years provides valuable context for understanding the 2025 results. Table 2 from the original source offers a detailed breakdown:
Table 2: 2022-2025 Part D Rating Distribution for PDPs
| Part D Rating | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|
| # of Contracts | % | Weighted by Enrollment | # of Contracts | |
| 5 stars | 10 | 18.52 | 0.93 | 2 |
| 4.5 stars | 5 | 9.26 | 4.74 | 7 |
| 4 stars | 14 | 25.93 | 36.21 | 7 |
| 3.5 stars | 20 | 37.04 | 52.84 | 11 |
| 3 stars | 3 | 5.56 | 3.84 | 16 |
| 2.5 stars | 2 | 3.70 | 1.44 | 4 |
| 2 stars | 0 | 0 | 0 | 4 |
| 1.5 stars | 0 | 0 | 0 | 1 |
| Total Rated Contracts | 54 | 100 | 52 | |
| Average Star Rating* | 3.70 | 3.25 | 3.34 | 3.06 |
* The average Star Rating is weighted by enrollment.
This table reveals a decrease in the average Star Rating for PDPs from 3.70 in 2022 to 3.06 in 2025. The percentage of contracts receiving 5 stars has also declined significantly, from 18.52% in 2022 to just 4.88% in 2025. Conversely, the percentage of contracts receiving 2.5 stars or less has increased over the same period. These trends highlight the increasing rigor of the Star Ratings system and the need for beneficiaries to carefully compare medicare part d drug plans to ensure they are enrolling in a high-performing option.
Identifying High-Performing 5-Star Part D Plans
While the overall average Star Rating for Part D plans has decreased, there are still standout plans achieving the highest level of quality. For 2025, two PDP contracts earned the prestigious 5-star rating, signifying exceptional performance across all measured domains. These plans are highlighted on the Medicare Plan Finder with a high-performing icon, making them easily identifiable for beneficiaries seeking top-tier coverage.
Table A3: PDP Contracts Receiving the 2025 High-Performing Icon
| Contract ID | Contract Name | Parent Organization | 10/2024 Enrollment | 5 Star Last Year |
|---|---|---|---|---|
| S3389 | UPMC HEALTH BENEFITS, INC. | UPMC Health System | 1,474 | No |
| S4501 | INDEPENDENT HEALTH BENEFITS CORPORATION | Independent Health Association, Inc. | 7,329 | Yes |
Opting for a 5-star Part D plan can offer numerous advantages, including potentially better customer service, more effective medication management programs, and higher overall satisfaction. When you compare medicare part d drug plans, prioritizing 5-star options can lead to a more positive and effective healthcare experience.
Understanding and Avoiding Consistently Low-Performing Plans
Just as it’s important to identify high-performing plans, it’s equally crucial to be aware of and potentially avoid consistently low-performing plans. CMS designates contracts with persistently poor quality ratings with a low-performing icon on the Medicare Plan Finder. For 2025, one PDP contract received this low-performing designation:
Table A4: Contracts Receiving the Low Performing Icon for the 2025 Star Ratings
| Contract ID | Contract Name | Parent Organization | Reason for Low-Performance Warning | 10/2024 Enrollment |
|---|---|---|---|---|
| S6946 | CLEAR SPRING HEALTH INSURANCE COMPANY | Group 1001 | Part D | 340,855 |
Enrolling in a low-performing plan may result in suboptimal care and services. When you compare medicare part d drug plans, be sure to check for the low-performing icon and consider plans with higher Star Ratings to ensure you receive the quality of care you deserve.
Factors Influencing Part D Star Ratings: Tax Status and Program Experience
The Star Ratings data also reveals interesting correlations between plan performance and organizational characteristics, such as tax status and years of experience in the Medicare program.
Tax Status: Non-profit organizations tend to achieve higher Star Ratings compared to for-profit organizations. For PDPs in 2025, approximately 41% of non-profit PDPs received four or more stars, whereas only 17% of for-profit PDPs reached this level. This suggests that the organizational mission and financial structure may play a role in the quality of care delivered. When you compare medicare part d drug plans, considering the tax status of the parent organization might provide an additional layer of insight.
Table 4: Distribution of 2025 Part D Ratings for For-profit and Non-profit PDPs*
| 2025 Part D Rating | Number of Contracts that are For-Profit | % For-Profit | Weighted By Enrollment For-Profit | Number of Contracts that are Non-Profit | % Non-Profit | Weighted By Enrollment Non-Profit |
|---|---|---|---|---|---|---|
| 5 stars | 1 | 4.35 | 0.01 | 1 | 5.88 | 1.27 |
| 4.5 stars | 2 | 8.70 | 0.46 | 4 | 23.53 | 19.02 |
| 4 stars | 1 | 4.35 | 3.48 | 2 | 11.76 | 9.09 |
| 3.5 stars | 6 | 26.09 | 48.51 | 4 | 23.53 | 21.96 |
| 3 stars | 5 | 21.74 | 8.45 | 5 | 29.41 | 47.94 |
| 2.5 stars | 6 | 26.09 | 30.03 | 1 | 5.88 | 0.73 |
| 2 stars | 2 | 8.70 | 9.06 | 0 | 0.00 | 0.00 |
| Total Rated Contracts | 23 | 17 |
*One PDP is missing information about tax status.
Program Length: While the relationship is less pronounced for PDPs due to fewer plans with limited program experience, experience in the Medicare program generally correlates with higher Star Ratings for MA-PD plans. For PDPs, the data is less conclusive, but it’s worth noting that the plan with the least experience (fewer than 5 years) received a 2-star rating. When you compare medicare part d drug plans, considering the longevity and track record of a plan within the Medicare program can be a helpful factor.
Table 6: Distribution of 2025 Part D Ratings by Length of Time in Program for PDPs
| 2025 Part D Rating | Number of Contracts with Fewer than Five Years | Percent Fewer than Five Years | Number of Contracts with Five years to Fewer than 10 Years | Percent Five Years to Fewer than 10 Years | Number of Contracts with 10 or More Years | Percent 10 or More Years |
|---|---|---|---|---|---|---|
| 5 stars | 0 | 0.00 | 1 | 33.33 | 1 | 2.70 |
| 4.5 stars | 0 | 0.00 | 1 | 33.33 | 5 | 13.51 |
| 4 stars | 0 | 0.00 | 0 | 0.00 | 3 | 8.11 |
| 3.5 stars | 0 | 0.00 | 1 | 33.33 | 9 | 24.32 |
| 3 stars | 0 | 0.00 | 0 | 0.00 | 11 | 29.73 |
| 2.5 stars | 0 | 0.00 | 0 | 0.00 | 7 | 18.92 |
| 2 stars | 1 | 100.00 | 0 | 0.00 | 1 | 2.70 |
| Total Rated Contracts | 1 | 3 | 37 |
Average Star Ratings Across Part D Measures: Areas for Improvement
Analyzing the average Star Ratings for individual Part D measures provides insights into specific areas of plan performance. Tables 8 and 9 from the original source detail these measure-specific ratings:
Table 9: 2022-2025 Average Star Rating by Part D Measure for PDPs
| Measure | 2022 PDP Average Star | 2023 PDP Average Star | 2024 PDP Average Star | 2025 PDP Average Star |
|---|---|---|---|---|
| Call Center – Foreign Language Interpreter and TTY Availability | 4.2 | 4.1 | 3.6 | 3.6 |
| Complaints about the Plan | 4.8 | 4.4 | 4.6 | 4.6 |
| Members Choosing to Leave the Plan | 4.2 | 4.0 | 3.9 | 3.7 |
| Drug Plan Quality Improvement | 4.1 | 2.2 | 3.0 | 3.0 |
| Rating of Drug Plan | 3.8 | 3.3 | 3.4 | 3.5 |
| Getting Needed Prescription Drugs | 3.9 | 3.5 | 3.5 | 3.7 |
| MPF Price Accuracy | 3.3 | 3.5 | 3.6 | 3.1 |
| Medication Adherence for Diabetes Medications | 3.9 | 2.9 | 2.6 | 2.4 |
| Medication Adherence for Hypertension (RAS antagonists) | 3.5 | 2.7 | 2.6 | 2.9 |
| Medication Adherence for Cholesterol (Statins) | 3.6 | 3.1 | 3.0 | 2.9 |
| MTM Program Completion Rate for CMR | 3.7 | 3.1 | 3.2 | 3.0 |
| Statin Use in Persons with Diabetes (SUPD) | 3.3 | 2.9 | 2.4 | 2.7 |
Several key measures consistently show average ratings below 4 stars, indicating areas where Part D plans could improve. Medication adherence for diabetes, hypertension, and cholesterol medications, along with MTM program completion rates, consistently receive moderate average ratings. This suggests that while plans perform reasonably well in these areas, there is room for improvement in ensuring patients adhere to their prescribed medications and fully utilize medication therapy management programs. MPF (Medicare Plan Finder) price accuracy also shows fluctuations and a slightly lower average rating in 2025, highlighting the importance of verifying pricing information directly with plans.
Conversely, measures like “Complaints about the Plan” and “Call Center – Foreign Language Interpreter and TTY Availability” tend to have higher average ratings, suggesting stronger performance in customer service and accessibility. When you compare medicare part d drug plans, examining these measure-level ratings can help you identify plans that excel in the areas most important to your individual needs and preferences.
How to Compare Medicare Part D Plans Using Star Ratings Effectively
The Star Ratings are a powerful tool to compare medicare part d drug plans and make informed enrollment decisions. Here’s how to use them effectively:
- Start with the Medicare Plan Finder: Visit the official Medicare Plan Finder tool on Medicare.gov. This tool integrates the Star Ratings directly into plan listings, allowing you to see ratings alongside cost, coverage, and formulary information.
- Filter by Star Rating: Utilize filters within the Plan Finder to specifically search for plans with 4 or 5 stars. This will help you quickly identify higher-quality options.
- Consider Overall and Measure-Specific Ratings: While the overall Star Rating provides a general assessment of plan quality, delve into the measure-specific ratings that are most relevant to you. For example, if medication management is crucial, pay close attention to medication adherence and MTM program ratings.
- Balance Ratings with Other Factors: Star Ratings are just one piece of the puzzle. Compare medicare part d drug plans not only on quality but also on factors like:
- Premiums and Costs: Ensure the plan is affordable for your budget.
- Formulary Coverage: Verify that your essential medications are covered and at what cost-sharing tier.
- Pharmacy Network: Check if your preferred pharmacies are in the plan’s network.
- Specific Benefits: Consider any unique benefits offered by different plans.
- Read Plan Details and Reviews: Once you’ve narrowed down your options based on Star Ratings and other factors, review the detailed plan documents and consider reading independent reviews or testimonials to gain a more comprehensive understanding.
By strategically using the Star Ratings in conjunction with other plan details, you can confidently compare medicare part d drug plans and select the option that best meets your healthcare needs and preferences.
Conclusion: Leveraging Star Ratings for Informed Part D Plan Selection
The 2025 Medicare Part D Star Ratings provide valuable data for beneficiaries seeking to compare medicare part d drug plans and make informed enrollment decisions. While the average Star Rating for PDPs has declined slightly, the system continues to highlight high-performing plans and identify areas for improvement across the industry. By understanding how to interpret and utilize these ratings, individuals can prioritize quality when choosing their Medicare Part D coverage, leading to better health outcomes and greater satisfaction with their prescription drug benefits. Take advantage of the Medicare Plan Finder and the wealth of information provided by the Star Ratings to make confident and well-informed choices during the upcoming enrollment period.
References
[1] See also the Announcement of Calendar Year (CY) 2025 Medicare Advantage (MA) Capitation Rates and Part C and Part D Payment Policies, page 130 at https://www.cms.gov/files/document/2025-announcement.pdf.
[2]https://www.federalregister.gov/documents/2020/06/02/2020-11342/medicare-program-contract-year-2021-policy-and-technical-changes-to-the-medicare-advantage-program.
[3] Percentages in the tables may not sum to 100 due to rounding.
[4] The qualifying extreme and uncontrollable circumstances for the 2023 performance period include severe storms, straight-line winds, and tornadoes in Mississippi, Typhoon Mawar in Guam, wildfires in Hawaii, and Hurricane Idalia in Florida and Georgia. See the 2025 Rate Announcement at https://www.cms.gov/files/document/2025-announcement.pdf.
[5] 42 C.F.R. §§ 422.166(h)(1)(i), 423.186(h)(1)(i).
[6] 42 C.F.R. §§ 422.166(h)(1)(ii), 423.186(h)(1)(ii).
