AB 1048 California Assembly · 2025-2026 Regular Session

Workers' compensation.

Summary

Existing law establishes a workers' compensation system, administered by the Administrative Director of the Division of Workers' Compensation, to compensate an employee for injuries sustained in the course of employment. Existing law requires an employer to provide medical, surgical, chiropractic, acupuncture, and hospital treatment that is reasonably required to cure or relieve the injured worker from the effects of the injury. Existing law requires every contracting agent, that sells, leases, assigns, transfers, or conveys its list of contract health care providers and their contracted reimbursement rates to a payor, to comply with certain requirements. Existing law also requires a payor to, among other things, provide an explanation of benefits or explanation of review that identifies the name of the network that the payor has an agreement with that entitles them to pay a preferred rate for the services rendered. This bill would require the explanation of review or explanation of benefits to include the state assigned medical provider network identification number and an email address that the rendering medical provider may use to request a copy of the underlying contract that entitles them to take the preferred rate. The bill would state that disclosure of a medical provider network does not satisfy this requirement. The bill would require the payor, upon request, to provide the rendering provider or their agent with a copy of the underlying contract once per 365-day period. Existing law requires each employer to establish a utilization review process to review and approve, modify, or deny treatment recommendations and establishes an independent medical review process to resolve disputes over a utilization review decision. Existing law requires various requirements to be met in determining whether to approve, modify, or deny requests by a physician for medical services. This bill would require a request for authorization of medical services by a physician to be signed by that physician, and would authorize a request to be sent via mail, fax, or electronic methods, as specified. The bill would make other conforming changes.

Bill status passed 3 of 5 stages cleared

Introduction

Feb 2025

Committee Review

Aug 2026

Assembly Passage

Jun 2025

Senate Passage

Governor

Introduced Feb 20, 2025 Last action Aug 13, 2026

Maddy AI version diff · 6 comparisons

What changed between versions

01/22/26 - Amended Senate → 06/15/26 - Amended Senate · 6 edits · Jun 15, 2026

MODERATE

The June 15, 2026 Senate amendment to AB 1048 adds a new amendment to Labor Code Section 4609, which imposes disclosure requirements on contracting agents that sell or transfer lists of contracted health care providers and their reimbursement rates to payors. The bill also clarifies the contact method for requesting underlying contracts (email address instead of phone number), fixes drafting errors in Section 4603.3, and adds a requirement that payors provide a copy of the underlying contract upon request once per 365-day period.

Scope change

The bill's scope expanded to cover contracting agents and payors under Section 4609, adding new disclosure obligations when provider lists and contracted rates are sold or transferred. The existing Section 4603.3 changes were refined but not substantially altered in scope.

SCOPE

The bill now amends Labor Code Section 4609 in addition to Sections 4603.2, 4603.3, and 4610. This expands the bill's reach to contracting agents that sell, lease, assign, transfer, or convey lists of contracted health care providers and their reimbursement rates to payors.

The digest now references 'explanation of review or explanation of benefits' (adding explanation of benefits) as the document that must include underlying contract information, broadening which types of billing explanations are covered.

REQUIREMENT

New Section 4609 requirements: contracting agents must disclose whether provider lists may be sold or transferred to other payors (including workers' compensation or auto insurers), what specific practices payors use to actively encourage employees to use contracted providers, whether payors may claim contracted rates without active encouragement, and must provide a summary of all payors currently eligible to claim a provider's contracted rate within 15 business days of a written request.

In Section 4603.3, the contact information required in the explanation of review for requesting an underlying contract was changed from 'an address and phone number' to 'an address and email address.'

The digest now states that the bill would require the payor, upon request, to provide the rendering provider or their agent with a copy of the underlying contract once per 365-day period, making this an explicit obligation on the payor rather than just a right of the provider.

TECHNICAL

Fixed drafting errors in Section 4603.3: 'If the contract is not received by the provider sent to the rendering provider' was corrected to 'If the contract is not sent to the rendering provider or their agent within 30 business days.'

09/05/25 - Amended Senate → 01/22/26 - Amended Senate · 7 edits · Jan 22, 2026

MODERATE

AB 1048 was significantly expanded in scope, now amending three Labor Code sections (4603.2, 4603.3, and 4610) instead of two (4603.3 and 4603.6). The bill adds comprehensive utilization review requirements under Section 4610, incorporates the full text of Section 4603.2 covering payment timelines and penalties, and removes the independent bill review provisions that were previously included. Changes to the contract disclosure requirement in Section 4603.3 are more modest, adding a definition of 'underlying contract,' requiring a network identification number on explanations of review, and limiting contract copies to the rendering provider or their agent within a 365-day window.

SCOPE

Section 4610 of the Labor Code is now amended, adding comprehensive utilization review requirements including: a 30-day window after injury where treatment is exempt from prospective review; a list of services requiring prospective authorization (pharmaceuticals, surgery, psychological treatment, home health care, imaging, durable medical equipment over $250, electrodiagnostic medicine); a requirement that utilization review processes be accredited by an independent nonprofit organization (URAC designated as default); a prohibition on financial incentives to physicians based on modification or denial rates; and a ban on insurers referring utilization review to entities in which they hold a financial interest without prior disclosure.

REQUIREMENT

Section 4603.2 is now included in full, establishing payment timelines (45 days for private employers, 60 days for governmental entities), a 12-month deadline for submitting payment requests, a 15 percent penalty plus interest for late payments, NPI number requirements on billing, protections against duplicate submission penalties, and a second review process with a 90-day request window.

Section 4603.3 now requires the explanation of review to include the state assigned medical provider network identification number applicable to the bill.

A new provision limits contract disclosure: only the rendering provider or their agent may be provided a copy of the underlying contract, and only within a 365-day period.

DEFINITION

Section 4603.3 now defines 'underlying contract' as the contract associated with the tax identification number of the rendering medical provider and the medical provider network listed on the explanation of review, providing a clearer standard for which contract must be disclosed.

ENFORCEMENT

The automatic reprocessing and payment trigger in Section 4603.3 was changed from 'if the contract is not received by the provider within 30 business days' to 'if the contract is not sent to the rendering provider or their agent within 30 business days,' shifting the obligation from the provider receiving it to the payer sending it.

The entire independent bill review framework previously in Section 4603.6 was removed, including: the definition expanding 'payment dispute' to include contract disputes involving discounts from the official medical fee schedule; the requirement that independent bill review organizations provide the medical provider contract when upholding a discount or reduction; the fee structure for independent bill review; and the appeal process to the appeals board.

04/10/25 - Amended Assembly → 09/05/25 - Amended Senate · 5 edits · Sep 5, 2025

MODERATE

The Senate amendment significantly expands AB 1048 by adding new requirements under Labor Code Section 4603.3 in addition to the existing Section 4603.6 changes. The new provisions require employers to provide specific contract information and contact details when a medical bill is discounted or denied based on a contract, explicitly state that merely disclosing a provider network is insufficient, and create an automatic remedy where the bill must be paid at official fee schedule rates if the contract is not produced within 30 business days. This gives medical providers a direct enforcement tool to obtain the actual contracts being used against them.

SCOPE

The bill now amends Labor Code Section 4603.3 in addition to Section 4603.6, expanding its scope from independent bill review procedures to also cover the initial explanation of review that employers must provide when paying, adjusting, or denying medical bills.

REQUIREMENT

When an employer adjusts, changes, or denies a billed item based on a contract, the explanation of review must now include specific information on the underlying contract and contact information (address and phone number) for whom the medical provider may contact to receive a copy of the relevant, applicable contract.

The bill explicitly states that disclosure of a medical provider network does not satisfy the requirement to provide contract information. Employers cannot simply point to a network agreement; they must identify and make available the specific contract relied upon.

ENFORCEMENT

If the medical provider does not receive the contract within 30 business days of requesting it, the bill shall be automatically reprocessed and paid at rates mandated by the official medical fee schedule. This creates a concrete financial consequence for employers who fail to produce the contract.

TECHNICAL

The original Section 4603.6 amendments (independent bill review procedures, payment dispute definitions including contract disputes, and requirements for independent reviewers to produce contracts) are retained with no substantive changes, but renumbered as the second section of the bill.

03/24/25 - Amended Assembly → 04/10/25 - Amended Assembly · 7 edits · Apr 10, 2025

MODERATE

The April 10 amendment to AB 1048 removes a standalone legislative intent section, adds a new exemption allowing independent bill review organizations to withhold contracts the medical provider is not a party to, clarifies that multiple contracts may be referenced, and fixes garbled language in the appeals provision. The fiscal committee answer also changed from 'no' to 'yes,' indicating the bill now carries a fiscal impact.

SCOPE

Removed the standalone Section 1 that stated the Legislature's intent to enact legislation improving transparency and accountability in contracts between payers and medical providers in workers' compensation. The bill now only amends Labor Code Section 4603.6.

ELIGIBILITY

Added new subdivision (f)(2) which states that the independent bill review organization is not required to provide the medical provider with a contract to which the medical provider is not a party. This creates an exemption from the transparency requirement for third-party contracts.

REQUIREMENT

Changed 'the contract relied upon' to 'the medical provider contract or contracts relied upon' in subdivision (f)(1), clarifying that multiple contracts may be at issue and specifying they must be medical provider contracts.

Changed the remedy language from 'payment consistent with the official medical fee schedule' to 'payment for the disputed medical treatment bill that is consistent with the official medical fee schedule,' narrowing the scope of what must be paid.

TECHNICAL

Fixed garbled language in subdivision (h) that read 'In no event shall the The appeals board or any higher court shall not make a determination' to the corrected 'The appeals board or any higher court shall not make a determination of ultimate fact contrary to the determination of the bill review organization.'

Changed 'his or her their powers' to 'their powers' in subdivision (g)(1) for gender-neutral language.

FISCAL

Fiscal committee answer changed from 'no yes' to 'yes,' indicating the bill now has a fiscal impact requiring appropriation review.

02/20/25 - Introduced → 03/24/25 - Amended Assembly · 5 edits · Mar 24, 2025

MODERATE

AB 1048 was transformed from a purely declaratory bill (stating legislative intent to improve transparency in workers' compensation contracts) into operative legislation that amends Labor Code Section 4603.6. The amendment adds a new definition expanding 'payment dispute' to include contract disputes over discounts from the official medical fee schedule, and requires independent bill review organizations to disclose the specific contract they relied on when upholding a discount or reduction - awarding the provider the full fee schedule amount if no valid contract can be produced.

Scope change

The bill's scope expanded dramatically from a non-binding statement of legislative intent with no operative effect to actual amendments to Labor Code Section 4603.6 that create new definitions, impose disclosure requirements on independent bill review organizations, and establish a remedy (full fee schedule payment) when payers cannot produce valid contracts supporting their discounts.

SCOPE

The bill went from having no operative provisions (only a statement of legislative intent) to actually amending Labor Code Section 4603.6, making it enforceable law rather than a placeholder for future legislation.

DEFINITION

New subsection (a)(2) defines a 'payment dispute' to include a contract dispute involving any discount or reduction from the official medical fee schedule that was applied to a medical treatment bill. This expands the scope of disputes eligible for independent bill review.

REQUIREMENT

New subsection (f) requires that when an independent bill review upholds a percentage discount or reduction, the reviewer must provide a written decision to the medical provider that includes the specific contract relied upon. If the payer cannot produce a valid contract justifying the discount, the reviewer must award the provider payment consistent with the official medical fee schedule.

TECHNICAL

Gendered language 'his or her' was changed to 'their' in the appeal grounds provision (subsection g)(1).

FISCAL

The fiscal committee designation changed from 'no' to 'yes,' indicating the amendment now has a fiscal impact requiring review by the fiscal committee.

Floor votes · Assembly Jun 4, 2025

How they voted

75–0

Passed · 3 other

Total votes 78

Jun 4, 2025

D Democratic59

58 Yea 1

98% Yea

R Republican19

17 Yea 2

89% Yea

Vote distribution

All Yea All Nay Mixed No data

Full legislative history

Actions timeline

Total actions

Key actions

Committee

Amendments

Aug 13, 2026

Upper · Passed

In committee: Held under submission.

upper

Jun 29, 2026

Committee

In committee: Referred to APPR. suspense file.

upper

Jun 15, 2026

Upper · Passed

Read second time and amended. Re-referred to Com. on APPR.

upper

Jun 11, 2026

Introduced

From committee: Amend, and do pass as amended and re-refer to Com. on APPR. (Ayes 5. Noes 0.) (June 10).

upper

May 27, 2026

Committee

Re-referred to Com. on L., P.E. & R.

upper

Jan 22, 2026

Introduced

From committee chair, with author's amendments: Amend, and re-refer to committee. Read second time, amended, and re-referred to Com. on RLS.

upper

Sep 8, 2025

Committee

Re-referred to Com. on RLS.

upper

Sep 8, 2025

Committee

Re-referred to Com. on L., P.E. & R. pursuant to Senate Rule 29.10(b).

upper

Sep 8, 2025

Committee

Re-referred to Com. on RLS. pursuant to Senate Rule 29.10(b).

upper

Sep 5, 2025

Upper · Passed

Read third time and amended. Ordered to second reading.

upper

Aug 19, 2025

Upper · Passed

From committee: Be ordered to second reading pursuant to Senate Rule 28.8.

upper

Jul 9, 2025

Upper · Passed

From committee: Do pass and re-refer to Com. on APPR. (Ayes 5. Noes 0.) (July 9). Re-referred to Com. on APPR.

upper

Jun 18, 2025

Committee

Referred to Com. on L., P.E. & R.

upper

Jun 4, 2025

Lower · Passed

Read third time. Passed. Ordered to the Senate. (Ayes 76. Noes 0. Page 2057.)

lower

May 23, 2025

Lower · Passed

From committee: Do pass. (Ayes 12. Noes 0.) (May 23).

lower

May 21, 2025

Committee

In committee: Set, second hearing. Referred to APPR. suspense file.

lower

May 14, 2025

Lower · Passed

In committee: Set, first hearing. Hearing canceled at the request of author.

lower

Apr 23, 2025

Lower · Passed

From committee: Do pass and re-refer to Com. on APPR. (Ayes 17. Noes 0.) (April 23). Re-referred to Com. on APPR.

lower

Apr 21, 2025

Committee

Re-referred to Com. on INS.

lower

Apr 10, 2025

Introduced

From committee chair, with author's amendments: Amend, and re-refer to Com. on INS. Read second time and amended.

lower

Mar 25, 2025

Committee

Re-referred to Com. on INS.

lower

Mar 24, 2025

Introduced

From committee chair, with author's amendments: Amend, and re-refer to Com. on INS. Read second time and amended.

lower

Mar 24, 2025

Committee

Referred to Com. on INS.

lower

Feb 21, 2025

Lower · Passed

From printer. May be heard in committee March 23.

lower

1 primary · 0 co-sponsors