Annual report · 2026-02-15Overview
The 2025 Healthcare Denial Trends Report synthesizes published MGMA, HFMA, and CMS data with anonymized claim records from Medonix's founding cohort, full calendar year 2025. Industry findings and cohort observations are reported separately. Every claim in the cohort was tracked from submission through final disposition (paid, denied, appealed, written off), with denial reasons categorized by CARC and RARC codes.
The dominant 2025 trend was the rise of prior-auth denials (CO-197) across commercial payers, particularly BlueCross BlueShield plans and UnitedHealthcare. Procedural specialties (cardiology, orthopedics, gastroenterology) absorbed the bulk of the shift. Behavioral health saw a similar but smaller impact concentrated in IOP / PHP levels of care.
Cost-per-denial (measured as the operational cost to work an appeal plus the time-value of delayed cash) averaged $43.20 across the cohort, up from $38.60 in 2024. The aggregate U.S. healthcare write-off estimate, extrapolated from cohort data, sits at $128B annually, a 7.4% YoY increase.
Key findings
- ✓Top denial reason: CO-16 (information missing) at 21.4% of total, down from 23.8% in 2024.
- ✓Fastest-growing denial reason: CO-197 (prior-auth absent) at +14% YoY, concentrated in commercial plans.
- ✓BCBS plans denied at 1.6× the rate of CMS Medicare; commercial-heavy practices saw the highest aggregate denial rates.
- ✓Appeal-overturn rate held at 64% across all denials; CO-197 overturn rate at 58% (lower than category average).
- ✓Aggregate U.S. write-off estimate: $128B annually, up 7.4% YoY.
What is in the report
- Top 10 denial reasons with year-over-year delta
- Payer-specific denial behavior (BCBS, UHC, Aetna, Cigna, Humana)
- Specialty denial-rate distribution
- Appeal-overturn rates by denial reason
- Cost per denial and aggregate U.S. write-off estimate
Methodology
Industry denial trends sourced from MGMA Annual Benchmark Survey, HFMA Denial Trends Index, and CMS public claim datasets. Medonix cohort observations drawn from anonymized claim records across our founding U.S. client cohort, calendar year 2025. Denial categorization based on CARC primary code, with RARC secondary. Aggregate U.S. extrapolation uses CMS National Health Expenditure data as denominator. Industry and cohort figures reported separately throughout.
Citation: Medonix Research, "2025 Healthcare Denial Trends Report," 2026.