How The Best Medicare Insurance Companies Were Chosen

Each year, the Centers for Medicare & Medicaid Services (CMS) reviews every Medicare Advantage contract based on numerous quality criteria. A contract refers to either a specific Medicare Advantage plan or a collection of similar plans from the same insurer. CMS assigns an overall rating to each contract, using a scale from 1 to 5 stars, with 5 stars representing the highest performance.

In its current directory of Medicare Advantage plans, U.S. News included the CMS star rating tied to the contract each plan is part of. Since CMS does not release quality scores for individual plans, all plans under the same contract share the same rating.

Over 30 quality measures from CMS were picked to help rate Medicare Advantage plans. Each one was given a different level of importance based on how scores have changed in the past, how useful the measure is to people, and whether the health plan can directly affect the result. For example, managing high blood pressure was considered more important because it affects a lot of people.

How Ratings Were Calculated

The text details the selection of 34 CMS quality metrics. Specifically, 25 CMS measures assessed Part C coverage, while 12 CMS measures evaluated Part D coverage. Due to three shared measures across both Part C and Part D, a total of 34 unique measures were utilized, instead of a potential 37, for evaluating Medicare Advantage plans offering both Part C and Part D benefits.

Each measure in the table was given a specific weight, which sometimes differed from the weighting used by CMS when calculating star ratings for Medicare Advantage plans. U.S. News determined these weights by evaluating how relevant each measure is to consumers, how much influence insurance companies have over their results, and how much variation in performance was observed among different insurers. If a measure showed little difference in outcomes over the past four years—indicating limited performance variation—it was assigned a lower weight in the analysis.

U.S. News determined each contract’s score using its own rating method. This process involved multiplying the U.S. News-assigned weight of each performance measure by the corresponding star rating given by CMS, then dividing that total by the sum of the weights for all applicable measures with CMS ratings.

To calculate an insurance company’s overall rating, U.S. News then averaged the ratings of all its Medicare Part C contracts—whether they included Part D coverage or not—while factoring in the number of enrollees. This was done by taking the score for each contract, multiplying it by the number of members aged 65 and older enrolled as of December 2023 (as reported by CMS), summing the results across all contracts from that insurer, and dividing by the total number of enrollees. This approach gave more weight to contracts serving a larger number of people, producing a final national rating that reflects both performance and reach.

To identify the Best Medicare Advantage Companies at the national level, insurers had to meet two criteria: they needed to serve at least 1,000 Medicare beneficiaries in 10 or more states or U.S. territories, and their overall enrollment-weighted rating had to be 3.8 or higher.

This process was also applied individually to each state and territory. In these local evaluations, insurers qualified for recognition if they covered at least 1,000 beneficiaries in the specific area and earned a rounded, enrollment-adjusted rating of 3.8 or above for that population.

For companies offering stand-alone Medicare Part D plans, U.S. News applied the same evaluation steps used for Medicare Advantage plans, but only using data from Part D-only contracts. This analysis helped identify the top Medicare Part D providers both nationwide and within individual states and territories.

To qualify for national recognition, a company needed to have at least 1,000 enrollees in 10 or more different states or territories and achieve a rounded, enrollment-weighted average rating of 3.0 or higher. At the state or territory level, eligibility required at least 1,000 Part D enrollees within that specific region, along with a rounded average rating of 3.0 or above for those members.

Specific Categories

U.S. News also ranked insurers in four specific award categories: three for Medicare Advantage—Screening & Prevention, Care Continuity, and Highest Satisfaction—and one for Medicare Part D—Highest Satisfaction.

To determine these rankings, U.S. News used 12 selected CMS quality measures and applied the same weighting system used in the overall ratings. Steps from the earlier methodology were repeated, but focused only on the measures relevant to each category.

Insurers were eligible for Medicare Advantage awards if they served at least 1,000 beneficiaries in 10 or more states or territories and received a rounded category rating of 3.8 or higher:

• Best for Screening & Prevention
• Best for Care Continuity
• Highest Satisfaction

For the Medicare Part D satisfaction award, insurers needed at least 1,000 beneficiaries in 10 or more jurisdictions and a rounded rating of 3.0 or higher based on measures D02 and D03.