California Claims Dispute & Statutory Guide

California workers' compensation medical treatment and billing are administered by the Department of Industrial Relations Division of Workers' Compensation (DWC). Disputes over medical billing amounts are strictly resolved through Second Review and Independent Bill Review (IBR) pursuant to Labor Code Section 4603.6.

Last Updated: 2026-03-05 • Framework: Workers' Compensation Dispute & Fee Schedule Guides (West Region)

Statutory Framework & Jurisdiction

Statutory no-fault workers' compensation system with employer Medical Provider Networks (MPNs) and standardized utilization review.

Official Medical Fee Schedule & Reimbursement Standards

name

Official Medical Fee Schedule (OMFS) - 8 CCR §§ 9789.10 - 9789.111

structure

RBRVS-based fee schedule updated annually with California-specific conversion factors for physician services, outpatient facilities, and inpatient hospitals.

electronic Billing

Mandatory e-billing compliance under California Labor Code Section 4603.4 and 8 CCR §§ 9792.5.0 - 9792.5.3

Preauthorization & Decision Point Review

protocol

Utilization Review (UR) governed by Labor Code § 4610. Providers submit DWC Form RFA (Request for Authorization).

deadlines

Prospective review decision must be communicated to the treating physician within 5 business days of receipt of complete clinical records.

dispute Mechanism

Independent Medical Review (IMR) through Maximus Federal Services (Labor Code § 4610.5)

Medical Billing & Appeals Procedure

timely Filing

12 months from the date of service (Labor Code § 4603.2(b)(2))

second Review

Mandatory prerequisite before IBR. Must be filed within 90 days of receipt of Explanation of Review (EOR) on DWC Form SBR-1.

independent Bill Review

Governed by Labor Code § 4603.6 and 8 CCR § 9792.5.4. Must be filed within 30 days of receipt of second review EOR with designated contractor (Maximus).

wcab Role

WCAB retains jurisdiction only over threshold legal liability issues (e.g., employment relationship, injury arising out of employment), not fee schedule calculations.

Critical Statutory & Dispute Deadlines

Dispute Phase / Trigger EventStatutory Timeline / Deadline
Initial Medical Bill Submission12 months from date of service
Payer Explanation of Review (EOR)45 days for paper bills; 15 days for compliant e-bills
Request for Second Review (SBR-1)90 calendar days from service of initial EOR
Payer Response to Second Review14 calendar days from receipt
IBR Application Filing30 calendar days from service of Second Review EOR

Required Evidentiary Filing Checklist

  • Complete CMS-1500 / UB-04 form with standard WC modifiers
  • Treating physician Doctor's First Report of Occupational Injury (Form 5021) or PR-2/PR-4 progress reports
  • Approved Request for Authorization (RFA) with UR approval letter where applicable
  • Itemized statement of contested codes, OMFS fee calculations, and ground-rule justifications
  • Copy of original EOR and Second Review EOR

Official Primary Sources & Legislative Authorities

California Labor Code Division 4 (Workers' Compensation and Insurance)
Agency / Body: California State Legislature (2024)
View Official Text
California Code of Regulations Title 8, Division 1, Chapter 4.5 (Division of Workers' Compensation)
Agency / Body: California DWC (2025)
View Official Text

Official Forms & Downloads for California

PDF455 B
Workers' CompensationCalifornia

CA DWC Form RFA Request For Authorization

Authorization Forms reference for California Workers' Compensation. Available for download.

Authority: California Regulatory Agency
PDF461 B
Workers' CompensationCalifornia

California DWC Form IBR - Application for Independent Bill Review

Official application form to request Independent Bill Review (IBR) through Maximus for disputed workers' compensation medical treatment and service billing under California Labor Code Section 4603.6.

Authority: California Division of Workers' Compensation (DWC)
Updated: 2026-02-15
PDF459 B
Workers' CompensationCalifornia

CA OMFS Official Medical Fee Schedule Summary

Fee Schedules reference for California Workers' Compensation. Available for download.

Authority: California Regulatory Agency

Governing Regulatory Authorities

California Division of Workers' Compensation (DWC)
Administration of State Workers' Compensation Laws
Official Portal →
Workers' Compensation Appeals Board (WCAB)
Judicial review of threshold compensation disputes
Official Portal →
Operational Support

Need Case Preparation Support in California?

Millennova Legal assists healthcare providers, revenue cycle teams, and law firms with comprehensive dispute documentation, arbitration filing bundles, and fee schedule calculations.

Request Dispute Consultation
Non-attorney arbitration support & claims documentation services.