How often do providers win federal IDR?

What the data actually says

Two figures matter. First, volume: more than 5.1 million disputes had been submitted to the federal process through January 31, 2026 — orders of magnitude above what the agencies projected when the process launched. Second, outcome: providers prevail in roughly 88% of determinations that reach a decision.

Why the win rate is that high

Federal IDR is baseball-style arbitration. The certified entity picks one of the two submitted offers; it cannot split the difference or write its own number. Plans frequently submit the QPA as their offer. The QPA is a median contracted rate, and for the hospital-based specialties that generate most disputes, the delivered service is often more complex than the median. A provider offer supported by acuity documentation, prior contracted rates, and market position beats a bare median more often than not.

Where disputes are actually lost

• Eligibility. The claim was covered by a state process, fell outside No Surprises Act scope, or the open negotiation period was never properly opened.
• Deadlines. The 4-business-day window to initiate after open negotiation closes is unforgiving, and it is the single most common way money disappears.
• Batching errors. Items grouped that do not meet the same-payer, related-code, consecutive-day conditions get the whole batch kicked.
• Thin submissions. An offer with no written rationale on the permitted factors gives the entity nothing to prefer over the QPA.

What the 2026 rule changed

The May 28, 2026 final rule cut the administrative fee from $115 to $15 per party per dispute, widened batching to consecutive-day items with the same service code up to 50 line items, and imposed 5-business-day eligibility review deadlines on certified entities. The practical effect is that lower-dollar claims that were previously uneconomic to dispute now clear the fee hurdle — and eligibility determinations come back faster, so a rejected dispute burns less calendar time.

The honest read

A high determination win rate does not mean every out-of-network claim should be filed. It means that disputes which survive screening and arrive with a documented offer are strongly favored. The work that produces recovery is upstream: routing each claim correctly, protecting the deadline, and building a record. That is the entire job.

Figures from CMS Federal IDR public use files and reports; volume through January 31, 2026. We update as new reporting periods are released.