Senator Grassley Opens Investigation Into UnitedHealth’s Medicare Billing Practices

Washington, D.C. – Senator Chuck Grassley (R-Iowa) has launched an inquiry into UnitedHealth Group, questioning whether the insurance giant has been stretching Medicare Advantage billing rules to its financial benefit. The central concern: Are diagnoses being documented to reflect true patient health, or to increase reimbursements from the Centers for Medicare & Medicaid Services (CMS)?

Medicare Advantage, which now covers more than 50% of all Medicare beneficiaries, uses risk adjustment payments to pay insurers more for covering patients with serious health conditions. But watchdogs have warned the system can be exploited. Some insurers, they say, use limited encounters like home health assessments to record high-severity conditions that may never be confirmed in a full medical exam.

“Taxpayers deserve to know whether these billing practices are padding corporate profits at Medicare’s expense,” Grassley said. “We need transparency and accountability to protect seniors and the program they depend on.”

The investigation follows years of scrutiny over upcoding practices in Medicare Advantage, where providers record more severe diagnoses than medically necessary, resulting in billions in excess payments. Federal agencies like the U.S. Department of Justice and the Office of Inspector General (OIG) have already pursued cases against multiple insurers for similar conduct.

UnitedHealth Group, one of the largest Medicare Advantage providers, maintains its coding aligns with CMS guidelines and accurately represents patient health. In a statement, the company said it is “fully cooperating” with Grassley’s office and remains “committed to delivering high-quality, compliant care to Medicare beneficiaries.”

Policy experts say the results of this inquiry could lead to legislative reforms, such as limiting diagnoses from home assessments unless confirmed during in-person clinical visits, a move that could reshape Medicare Advantage risk adjustment policies.