Healthcare executives spent the past two years blaming margin compression on the usual suspect: payers paying less. New benchmarking data suggests they have been looking in the wrong place. The money isn’t being cut at the negotiating table. It’s being lost after the work is already done.
A full-year analysis of more than 2,300 hospitals and roughly 375,000 doctors, published this spring by Kodiak Solutions, found that providers lost $48.4 billion in net revenue in 2025, not to rate cuts, but to denied claims and amounts they were owed and never collected. That figure is up from $38.6 billion a year earlier, a 25% jump in what the industry now calls revenue leakage: legally earned revenue that simply never arrives.
For the CEO of a health system or a multi-site specialty group that reframing matters. Reimbursement rates are largely outside an operator’s control. Leakage is not. And it concentrates in predictable places like high-acuity, authorization-heavy specialties where a single missing approval or miscoded encounter can erase the margin on an entire episode of care. It is no accident that operators running neurology billing services and other complex specialty lines have become the most vocal about the problem: their denial exposure per claim is among the highest in outpatient medicine, and the dollar value of each lost claim is large enough to move a P&L.
Why Small Denial Increases Cause Large Losses
The mechanics are deceptively quiet. Kodiak’s data shows the median final denial rate rising only modestly, from 2.5% to 2.7%, with the bad-debt rate ticking up from 1.1% to 1.3%. Those look like rounding errors. They are not.
The reason small rate changes produce billion-dollar swings comes down to who is denying and for what. Commercial payers, which reimburse at higher rates than government plans, drive the largest share of leakage. Clinical denials such as refusals tied to missing prior authorization or contested medical necessity, accounted for nearly the entire increase, and they are notoriously hard to win back. Providers overturned just over 42% of denials in 2025, down slightly from the year before. Roughly a third of “lost” revenue, in other words, is gone the moment the claim is rejected.
Independent estimates put the steady-state damage at 3% to 7% of net patient revenue permanently uncollected at many organizations. For a practice or system running on thin operating margins, a 3% to 5% leakage rate is frequently the difference between investing in growth and perpetually chasing money it has already earned.
Most Leakage Begins Before The Claim Is Filed
The most counterintuitive finding for executives is where leakage originates. By the time a denial surfaces in accounts receivable, the failure is months old. Most of it began at intake: an eligibility error, a demographic typo, a missing authorization, a weak point-of-service collection.
This is why the leaders pulling away from the pack are not the ones with the most aggressive collections teams. According to the benchmarking analysis, top-quartile performers combine fast clean-claim throughput, disciplined denial prevention, and rigorous front-end patient-pay processes. The differentiator is operational consistency, not back-end heroics.
The Specialties Most Exposed
The specialties that bleed most are the ones where clinical complexity and payer scrutiny intersect. Procedures requiring extensive documentation, frequent prior authorization, and precise diagnosis-to-procedure coding carry both the highest denial probability and the highest dollar value per claim.
Neurology sits squarely in that zone, and within it the sub-specialties are harder still. Epilepsy care is a representative case: long-term EEG monitoring, ambulatory studies, and the coding distinctions between routine and extended diagnostic services create exactly the documentation density payers scrutinize first. Practices that have invested in dedicated epilepsy billing services report markedly fewer first-pass denials on precisely these claim types. The lesson generalizes it as leakage is an operating model problem disguised as a billing problem.
Leakage As An Executive Metric
The strategic implication for leadership is straightforward. Net revenue leakage belongs on the executive dashboard alongside the metrics boards already watch. Days in A/R and net collection rate describe what happened after revenue moved through the system; they say nothing about where it broke. Treating leakage as a finance-department concern is how organizations keep chasing revenue that was never collectible to begin with.
The headwinds aren’t easing. Medicaid disenrollment and shifting payer mix are expected to push more cost onto self-pay patients, who already paid a smaller share of what they owed in 2025 than the year before. Medicare Advantage plans continue to deny at more than double the rate of traditional Medicare while paying more slowly. None of that is within an operator’s control.
What is within their control is whether earned revenue actually converts to collected revenue. The $48.4 billion the industry lost last year was not taken at the negotiating table. It leaked out through a thousand small operational gaps, and that, unlike reimbursement, is a problem executives can actually fix.
