How to read the California IDR market

California is one of the largest federal IDR markets in the CMS public files. For a provider group, the useful comparison is rarely the national average. The better question is how a payer behaves in the same state, service mix, and specialty lane.

The tables below show the payer, code, and IDR entity mix that shape California disputes. Use them to spot where an underpaid out-of-network book may deserve a closer NSA workflow review.

Top payers in California federal IDR disputes

PayerDisputesProvider win rate
Anthem Blue Cross28,48789%
Aetna11,99194.8%
BLUE SHIELD PPO8,53177.2%
UnitedHealthcare6,33386.1%
Cigna (cigna.com)5,37881.6%
Cigna / MultiPlan2,92282.5%
UMR1,53386.1%
UMR (clearhealthcloud.com)92087.9%

Top service codes in California

CodeServiceDisputesProvider win rate
99284Emergency department visit for the evaluation and management of a patient, which...16,03389.2%
99285Emergency department visit, high severity, requiring urgent evaluation14,43289.2%
85025Complete blood count (CBC) with automated differential6,52185.7%
36415Routine venipuncture (blood draw)5,89489.1%
99283Emergency department visit for the evaluation and management of a patient....4,10689.6%
80048Basic metabolic panel (8 blood chemistry tests)3,75785.4%
93005Electrocardiogram (ECG) tracing only, without interpretation3,40889.2%
80053Comprehensive metabolic panel (14 blood chemistry tests)3,02986%

Certified IDR entity mix

Certified IDR entityDisputesProvider win rateMedian award
Maximus Federal Services, Inc.6,30694.2%24.6x
Federal Hearings and Appeals Services, Inc.6,19786.4%2.5x
Island Peer Review Organization4,45499.2%4.9x
Provider Resources, Inc.4,33293.6%14.9x
C2C Innovative Solutions, Inc.3,99191.5%3.7x
MCMC Services, LLC3,05795.3%4.2x
EdiPhy Advisors, L.L.C.3,02097.4%4.5x

Open the live California dashboard

Use the data explorer to filter California by specialty, payer, and year, then compare the results with your own disputed claims.

View California IDR data

FAQ

How many federal IDR disputes are in California?

The California page currently shows 69,565 CMS disputes in the benchmark dataset.

What is the provider win rate in California?

The non-default provider win rate in California is 87.3% in this dataset.

Why can California differ from national IDR averages?

State, payer, service-code mix, and routing rules can change the economics of a dispute. That is why state-specific benchmarks are more useful than a single national win rate.

Related benchmarks

Sources and method

Data source: CMS Federal IDR public use files, coverage through 2025Q4; data build 2026-09-21. Counts are CMS dispute counts unless a table says line items. Win rates labeled non-default exclude payer no-show defaults. Award multiples are medians versus QPA. Dollar figures, where shown, are anchored estimates from CMS QPA-and-offer fields, not payment records. This page is informational, not legal or reimbursement advice.