California’s Subsequent Injuries Benefits Trust Fund (SIBTF) assessments have grown roughly 24 times over in a decade, from $35 million in FY 2014-15 to approximately $850 million today. A budget trailer bill released February 4 with the governor’s 2026-27 proposal would overhaul the fund’s eligibility rules, disability evaluation methodology, and offset provisions. The governor’s May Revise, due today, will signal whether the administration is holding firm on these reforms as the budget moves to conference committee.
The Department of Industrial Relations projects that without reform, annual employer assessments will reach $1.5 billion by FY 2029-30. The fund’s claims backlog now exceeds 30,000 pending cases, double the level five years ago, with some claimants facing processing delays of up to 10 years.
What the trailer bill changes
The reform targets four structural cost drivers.
Eligibility tightening. The bill redefines “labor disabling” to require proof that a pre-existing condition caused lost earnings, interfered with work activity, or demonstrably impaired the ability to work. Conditions managed by medication (controlled hypertension, treated sleep apnea) would no longer qualify. Workers who already hold 100% permanent disability awards would be barred from filing new SIBTF claims for additional PD benefits.
Disability rating overhaul. The bill overrules the Workers’ Compensation Appeals Board’s Todd v. SIBTF decision by mandating use of the combined values chart for permanent disability determinations involving multiple body parts. It also requires applying the whole person impairment percentage before the 1.4 modifier introduced by SB 863, making it harder to reach the 70% and 100% disability thresholds that drive the largest awards.
Neutral medical evaluations. The current system allows both sides to submit reports from their own medical experts. The trailer bill would replace this with neutral Qualified Medical Evaluator (QME) evaluations, aligning SIBTF proceedings with the standard workers’ comp medical-legal process.
Offset presumptions. New provisions create a presumption favoring offsets to prevent double recovery, with exemptions for military disability pensions and certain public assistance benefits.
The budget also includes $36.5 million and 177 new positions over five years to clear the claims backlog, a recognition that reform without processing capacity would not reduce the assessment trajectory.
Who it affects
Every California employer paying into the workers’ comp system bears a share of SIBTF assessments. Self-insured employers, including large corporate programs, public entities, and hospital systems, pay through a direct assessment factor on indemnity paid. Insured employers pay through carrier surcharges embedded in their premiums. Both groups have watched this line item grow faster than any other component of their WC cost structure.
The Assembly Budget Subcommittee No. 5 heard testimony on the staffing request on March 10. Labor groups are expected to push back on the 100% PD eligibility bar and offset presumptions as the bill moves through the budget conference process.
How it hits reserves
The reserve mechanism here is the expected claim ratio and cost allocation, not the development triangle. SIBTF assessments flow through as a component of allocated loss adjustment expense or as a separate line in the self-insured employer’s WC cost projection. When those assessments multiply 24 times in 10 years, any forward cost model that used historical assessment levels as a baseline is understating the run rate.
If the trailer bill passes intact, employers could see the assessment growth curve flatten as tighter eligibility and lower per-claim award amounts reduce the fund’s annual payout. If it stalls or gets stripped in conference committee, the DIR’s $1.5 billion projection becomes the working assumption. California’s recent 10.4% WCIRB pure premium increase already reflects some of this pressure from the insured side; the self-insured assessment is a parallel channel.
What this means for your next review
Model your WC cost projection under two scenarios: one where the trailer bill passes substantially as proposed and the assessment factor stabilizes, and one where reform fails and the DIR’s $1.5 billion projection holds. Ask your actuary to break out the SIBTF assessment as a separate line so the board can see the exposure independently of loss development. Watch whether the trailer bill survives the budget conference committee intact this summer, and update the scenario weights accordingly.