Neutral policy analysis · not marketing · not legal advice
Reading the CMS IDR Public Use Files: what the 2025 data shows
The Public Use Files are the closest thing to ground truth in this debate. Here is what they say, with the caveats they carry.
As of 2026-03-31 · 7 min read · Keyword: CMS IDR data 2025
Volume
Disputing parties initiated approximately 2.56 million federal IDR disputes in 2025, roughly 1.19 million in the first half and 1.37 million in the second, per CMS Public Use File supplemental data. For context, when the process launched federal officials had expected on the order of 17,000 disputes per year, so realized volume has run orders of magnitude beyond the original design.
Who prevails, and how often disputes are eligible
Per the CMS Q3–Q4 2025 supplemental background, providers and facilities were the prevailing party in approximately 85 percent of payment determinations in the last six months of 2025. The ineligibility rate declined to about 19 percent for that period, while payers challenged the eligibility of roughly 42 percent of initiated disputes. Award amounts vary widely by specialty.
As of the Q3–Q4 2025 PUF
These figures reflect 2025 data published in early-to-mid 2026 and will move as CMS releases new files (roughly quarterly). Any citation should carry its as-of date.
What the PUFs do not settle
The PUFs describe volumes and outcomes; they do not resolve the contested question of what IDR costs the system, which depends on assumptions about the counterfactual and about the QPA. Treat cost estimates as a separate, contested tier of evidence.
Sources & evidence tiers
- VerifiedCMS Federal IDR Public Use Files, 2025 (volumes, prevailing shares, ineligibility)
Figures are cited as of 2026-03-31 and reflect data available at that time. The IDR data environment moves quickly; verify current rules and figures with CMS and counsel.