Federal Enforcement Actions Against Medicare Advantage Plans.

Importance: Enrollment in Medicare Advantage (MA) plans continues to increase, now covering more than half of Medicare beneficiaries and receiving more than $494 billion in annual federal payment. Therefore, robust oversight is essential to monitor plans' adherence to federal standards and initiate enforcement actions when necessary to ensure program integrity and protect beneficiaries. Objective: To examine Centers for Medicare & Medicaid Services (CMS) enforcement actions against MA contracts and characteristics of contracts and beneficiaries involved with enforcement actions. Design, Setting, and Participants: This is a cross-sectional study of CMS enforcement actions against MA contracts that were preferred provider organizations or health maintenance organizations from 2010 to 2023. Data were analyzed from May 2025 to January 2026. Exposures: Enforcement actions, including civil money penalties, suspension of enrollment, and contract termination. Main Outcomes and Measures: The outcomes of interest were number of enforcement actions and contracts affected and mean monetary penalties per MA enrollee. Results: There were 1173 unique MA contracts and 844 enforcement actions from 2010 to 2023. A total of 493 unique MA contracts (42.0%) received an enforcement action during the study period. Most of enforcement actions originated from program audit (544 actions [64.5%]). Enforcement activity varied widely across years: in 2012, 100 contracts (19.2%) received monetary penalties, while only 5 contracts (0.9%) received such penalties in 2019. Most enforcement actions were monetary penalties (737 actions [87.3%]), with far fewer enrollment suspensions (99 actions [11.7%]) and contract terminations (8 actions [0.9%]). Financial penalties peaked at $6.50 per enrollee in 2019 and remained less than $3 in other years. Compared with contracts that did not receive enforcement actions, contracts that were terminated had lower star ratings (mean [SD], 2.5 [0.5] stars vs 3.6 [0.6] stars) and enrolled a much lower share of White beneficiaries (44.7% vs 68.7%); suspended contracts enrolled more dually eligible beneficiaries (28.9% vs 18.8%). Conclusions and Relevance: This cross-sectional study found that federal enforcement actions against MA plans were highly variable from year-to-year and imposed modest fines. Enforcement actions may be relatively modest in magnitude, raising concerns about their effectiveness in deterring nonadherence. The design of oversight and enforcement actions warrant further evaluation to determine what amount of enforcement actions are needed to protect patients and ensure plans meet federal standards.