Enrollees in traditional Medicare paid an additional $13.4 billion in premiums in 2025 due to overpayments by Medicare Advantage (MA) plans.[1][6] These higher Medicare Part B premium costs were borne mainly by seniors, with the average American senior paying about 10% more, or more than $200 a year.[1] The overpayments affected beneficiaries of both traditional MA plans and standard Medicare.[1] An investigation by the Joint Economic Committee of Congress, led by Rep. David Schweikert (R-AZ), attributed the overpayments to a tactic by health insurance companies to add diagnoses to increase payments for MA members.[1] MedPAC estimates total MA overpayments at $84 billion in 2025, a 20% increase per enrollee over traditional Medicare.[2][5][6] In 2025, almost 35 million seniors were enrolled in MA.[2] AHIP denies the allegations and says the findings are based on flawed data and methodology.[1]