CMS Now Audits All 550-Plus Medicare Advantage Insurers Each Year for Coding Accuracy

The Centers for Medicare and Medicaid Services announced a sweeping expansion of its Medicare Advantage audit program in March 2026. Where the agency previously reviewed roughly 60 of the approximately 550 eligible health plan contracts each year, CMS now audits every eligible contract annually on a quarterly schedule.

The program is called Risk Adjustment Data Validation, or RADV. Under Medicare Advantage, the federal government pays private insurers higher monthly amounts for patients who are sicker, based on diagnosis codes the plans submit. RADV audits check whether those codes are backed by actual patient medical records. When records do not support a code, CMS can require the plan to repay the difference.

To handle the expanded workload, CMS grew its team of certified medical coders from about 40 to approximately 2,000. Plans also face larger record samples, between 35 and 200 enrollee files per contract scaled to plan size, compared with a flat 35 under the prior approach.

Payment Year 2020 audits are currently under way. Plans selected for review must submit supporting medical records by August 28, 2026. Plans seeking a hardship exception have until September 11.

CMS plans to initiate Payment Year 2021 audits in spring 2026 and Payment Year 2024 audits in August 2026, working through a years-long backlog.

For enrollees, RADV audits do not change day-to-day coverage. The practical effect is that plans found to have billed for unsupported diagnoses must return money to the federal government, reducing overpayments in a program covering more than 55 percent of all Medicare enrollees.