Carriers & the market
Federal Audit Estimates UnitedHealthcare of Wisconsin Owes at Least 46.9 Million Dollars in Medicare Advantage Overpayments
Auditors found medical records did not support diagnosis codes in 183 of 250 sampled enrollee-years that the plan submitted to determine its CMS payments.
By the Goodsurance editorial teamSeptember 16, 2026
A federal audit completed September 10, 2026, found that UnitedHealthcare of Wisconsin, Inc., received an estimated minimum of 46.9 million dollars in Medicare Advantage overpayments for policy years 2020 and 2021, according to the Department of Health and Human Services Office of Inspector General.
Auditors reviewed 250 enrollee-year records and found that 183, or about 73 percent, lacked adequate support in medical records for the diagnosis codes the plan submitted to CMS. Those codes are used in the Medicare Advantage risk-adjustment model, which sets monthly payments from CMS to plans based on projected enrollee health costs. Diagnoses not backed by documentation inflate those payments.
A federal audit says UnitedHealthcare of Wisconsin may owe at least 46.9 million dollars in Medicare Advantage overpayments for diagnoses records did not support.
Within the sample, unsupported codes produced 722,280 dollars in overpayments. OIG projected that figure across the broader enrollee population and estimated at least 46.9 million dollars in excess payments over the two-year audit period.
The OIG recommended that UnitedHealthcare of Wisconsin refund the 46.9 million dollars and strengthen internal compliance processes to prevent similar errors going forward.
The audit is one of several concurrent OIG reports examining how individual Medicare Advantage plan contracts handle diagnosis code submissions to CMS.
In plain words
The government's health care watchdog reviewed the UnitedHealthcare Medicare Advantage plan in Wisconsin. It found that most of the medical codes the plan sent to the government were not backed up by patient records. The plan used those codes to get paid more money from Medicare. The watchdog says the plan was overpaid by at least 46.9 million dollars and should pay it back.
Understand the basics first
Source: OIG HHS
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