The Medicare Advantage Cost Transparency Act seeks to enhance transparency within the Medicare Advantage program by amending the Social Security Act. This legislation mandates that, for plan years beginning on or after January 1, 2027, Medicare Advantage plans must include additional detailed information in their encounter data submissions for items and services provided to beneficiaries. Specifically, the required data includes the allowed amount for each item or service and the associated cost sharing , such as deductibles, copayments, and coinsurance. Additionally, plans must indicate whether the individual received an at-home health risk assessment during the plan year, differentiating between assessments furnished by entities with an ownership or control interest by the MA organization (specified assessment entities) and those without such a relationship.